Fourth Doctor

Filled with wanderlust and a renewed curiosity towards exploring time and space, the Fourth Doctor left all ties of his previous incarnation's exile behind on Earth, setting off to travel the universe, taking advantage of his freedom once more.

This incarnation of the Doctor initially travelled with Sarah Jane Smith and Harry Sullivan, but Harry chose to remain on Earth when the opportunity arose. The Doctor and Sarah continued on their adventures until the Doctor was summoned to Gallifrey, necessitating that he leave Sarah Jane behind as humans were not allowed on Gallifrey at the time.

After tangling with on Gallifrey when he tried to heal himself and renew his regeneration cycle, he met and travelled with Leela of the Sevateem. During his travels with Leela, the Doctor gained a new companion in the robot dog, K9. Returning once more to Gallifrey to stop an invasion of Vardans, Leela and the original K9 stayed behind there.

On the White Guardian's orders, the Doctor began looking for the Key to Time with fellow Time Lady Romana and K9 Mark II. Once that search was concluded, the Doctor and Romana went on the run from the Black Guardian. Not long after, Romana regenerated into a new body and continued to travel with the Doctor and K9. When they attempted to answer a Gallifreyan summons, the trio accidentally passed into the smaller universe of E-Space.

During his travels in E-Space, the Doctor gained a new companion in the teenaged mathematical genius Adric. Romana and K9 stayed behind in E-Space as the Doctor and Adric departed for N-Space. There, they encountered a Trakenite named Nyssa and a human named Tegan. The foursome successfully prevented the destruction of the universe by, but only at the cost of this incarnation's life.

The Doctor prepared for the worst when the Watcher, an entity born of his own immediate future, appeared to warn him of his demise. Due to the Master messing with the rotation controls for the Pharos radio telescope, the Doctor fell a great height. Suffering terrible injuries, he was assisted by the Watcher in his last moment, who joined with him and helped him regenerate into his next incarnation.

A day to come
The First Doctor would occasionally have premonitions of his future incarnations, (PROSE: A Big Hand for the Doctor) and there was a rumour that he was able to glimpse his first seven regenerations during a game of Eighth Man Bound. (PROSE: Christmas on a Rational Planet, Lungbarrow)

When the First Doctor learned that he was diverted from the South Pole by "forces from the future" to stop him from becoming an incarnation that would play a key role in a future conflict, he was informed by the Player that he would have "lots of new faces" before he regenerated into the incarnation involved in the conflict. (AUDIO: The Plague of Dreams)

The First Doctor was shown footage of the Fourth Doctor, as well as his ten other successors, by the Testimony when he expressed doubt over the Twelfth Doctor's identity. (TV: Twice Upon a Time)

During an encounter with the Eighth Doctor, the Third Doctor was told that he "[would] end [his time] by [his] own choice, in a noble cause". (PROSE: The Eight Doctors)

The Third Doctor briefly regenerated into his fourth incarnation after he fell off a roof during a struggle with the Nurazh. The Nurazh attempted to take over the dying Doctor's mind, but was unable to cope with two different versions of the Doctor at the same time and perished, healing the Doctor back to his third incarnation. Jo Grant saw the Fourth Doctor long enough to describe him to the Third Doctor as being "all teeth and curls". (PROSE: The Touch of the Nurazh)

The Third Doctor was later told by Sarah Jane Smith that she had been present during his regeneration, with the Doctor commenting that he became "teeth and curls" by studying Sarah Jane's hand movements. (TV: The Five Doctors)

Post-regeneration
The Third Doctor's death took place ten years after the radiation from the Great One's lair caused severe damage to his body. (PROSE: Love and War) He returned to Earth to end his time in the company of Sarah Jane and the Brigadier. K'anpo Rimpoche soon arrived and kick started the regeneration. (TV: Planet of the Spiders)

Once he had regenerated, the Doctor suffered delirium, mumbling random things from his past adventures, and was physically exhausted. He was put in sickbay, where medical officer Harry Sullivan kept watch on him. However, the Doctor managed to outwit him and get to his TARDIS to leave. (TV: Robot)

Slipping away from UNIT HQ, (PROSE: Doctor Who and the Face of Evil) the Doctor visited Pesca, (AUDIO: Doctor Who and the Pescatons) and a planet colonised by the Mordee expedition, and encountered the colony ship's powerful computer, Xoanon, which he repaired from damage Xoanon sustained, accidentally imprinted his own mind on the computer, leaving him with multiple personalities. (TV: The Face of Evil)

Returning to UNIT HQ, though still with situational awareness issues, the Doctor was asked by the Brigadier to help deal with the Think Tank and their K1 robot, which had gone insane from so many contradictory orders its programming should have prevented it from doing. Afterwards, he returned to travelling in his TARDIS, taking Sarah Jane and Harry with him, abandoning a UNIT dinner party at Buckingham Palace and leaving without telling the Brigadier. (TV: Robot)

The Nerva Beacon
Due to Harry's inadvertent interference with the helmic regulator, the TARDIS landed on Space Station Nerva, where humanity had been cryogenically suspended to await Earth's recovery from solar flares. There, the Wirrn wished to use the humans as food and incubators for their kind after the human race had destroyed their breeding colonies throughout the Andromeda galaxy in a thousand-year battle with them, sending them into space. Unable to reproduce without terrestrial colonies, they sent their queen to the Nerva Beacon, who birthed several larvae before she died from the Nerva Beacon auto-guard. The larvae began to feast on humans, absorbing their knowledge and their bodies. Luckily, Noah, a human was converted into a Wirrn, retained his strong will and tricked the Wirrn into a suicide. Afterwards, on behalf of the space station, the Doctor went down to Earth with Harry and Sarah Jane to fix the transmat relay, leaving the TARDIS on the station, while Vira, the station's first medtech, tended to waking the rest of her crew from their long sleep. (TV: The Ark in Space)

Once on Earth, they found the Sontaran Styre conducting experiments on humans as a prelude to an invasion. Caught in the wrong place at the wrong time, the Doctor was accused of murdering a GalSec officer among a crew who had been lured to the Earth and slowly picked off by Styre. After escaping them, he rescued Sarah from an experiment where her inner fears were used against her. Styre appeared to fatally shoot the Doctor as he fled, but the Doctor had nicked a piece of the Nerva's synestic locking system, which guarded him from injury.

Knowing a Sontaran would not refuse an opportunity to engage in mortal combat, the Doctor returned and challenged Styre to a duel. This wore him out and bought Harry enough time to remove a terullian diode bypass transformer from the ship that nurtured Styre with energy, making the energy feed on Styre instead. The Doctor went on to address the Marshal who had sent Styre to Earth. The Doctor defeated his plans by bluffing the Marshal to call off his attack, allowing the resettlement of Earth to proceed, and transmatted with his companions back to the space station to retrieve the TARDIS. (TV: The Sontaran Experiment)

Intercepting their transmat beam, the Time Lord Valyes appeared to the Doctor and forced him to undertake a mission on the Time Lords' behalf: prevent the creation of the Daleks or induce the Daleks to develop into less aggressive creatures. Valyes also gave the Doctor a Time Ring, which he could use to get back to his TARDIS. Upon their arrival on Skaro, the Doctor, Sarah Jane and Harry was caught up in a war between the Kaleds and Thals, with the Doctor being taken prisoner by the Kaleds with Harry after being separated from Sarah Jane. While being questioned, the Doctor met the creator of the Daleks, a scientist named Davros, attempting to genetically engineer the Kaleds as the effects of their weapons caused them to mutate, seeking to evolve their mutations into a perfect form. Despite respecting each other as scientists, the Doctor was unable to convince Davros to change the Daleks into better creatures.

When he revealed he knew of several defeats of the Daleks in the future due to faults in their design, the Doctor was forced to tell Davros of each failure the Daleks suffered, so that he could prevent them. Attempting to gauge the extent of his insanity, the Doctor posed a question to Davros, asking him what he would do if he possessed the power to end all other life. Davros's willingness to utilise such power horrified the Doctor, tempting him to cut off his life supports as a last resort of stopping his plans, but he was prevented from doing so by Nyder, and he was imprisoned. Escaping, the Doctor destroyed Davros' recording of the foreknowledge, thus keeping the future from changing for the worse.

The Doctor found little other option left than to ensure the Daleks would never exist, and had the opportunity to blow up the stock of embryonic Daleks that Davros had produced. However, he questioned if he had the right to destroy the Daleks, knowing that wiping out an entire species would make him just like them, and the fear of the Dalek had caused many worlds to ally with each other. With this in mind, the Doctor allowed the Dalek species to persist, and chose to stall their rise to power instead. Failing to listen to the Doctor's warnings, Davros found his own creations usurping him. Because they were programmed to acknowledge any creature as inferior to the Dalek, they deemed him unworthy to rule them. Fleeing after the Daleks killed Davros, the Doctor buried them and their factory underground, delaying their progression by a thousand years. (TV: Genesis of the Daleks)

After departing from Skaro, the Doctor, Sarah Jane and Harry became scattered across the Adelphine Cluster due to a temporal disruption interfering with the time ring. However, they were eventually united by the interventions of the Time Lords, who also provided them with a replacement time ring. (PROSE: A Device of Death)

Using the time ring, the Doctor, Sarah and Harry set off for Space Station Nerva. But instead, they arrived on the Desolii, a famous ghost ship, where they encountered friendly robots, microscopic psychiatrists and ghosts. (PROSE: The Last Thing You Ever See)

Due to the interference of the CIA, (PROSE: A Brief History of Time Lords) the Doctor, Harry, and Sarah Jane returned to the Space Station Nerva earlier in its time line, when it orbited Jupiter, which had a fifty-year assignment to guide space freighters. The TARDIS was travelling back through time to them, leaving them stranded until it arrived. While waiting for it to arrive, the Doctor became involved with stopping a Cyberman attack on Voga, the planet of gold, to keep the resource of their major weakness to a minimum in the Cyber-Wars. The Doctor ultimately stopped them from blowing up the planet, defeating them once more. Finally reunited with the TARDIS, the Doctor received a call for help from the Brigadier via a space-time telegraph. (TV: Revenge of the Cybermen)

Returning to UNIT
With the TARDIS still recovering from solar flare radiation, the Doctor took Sarah and Harry to 24th century Prague, where they visited a museum and discovered a dead body in one of the exhibits. The Doctor was accused of murder, but persuaded the police to allow him to take over the investigation. He and his two friends discovered nanoprobes had been in-bedded into the city, and further investigating soon led him to the killer. (PROSE: Nanomorphosis)

While answering the Brigadier's distress call, the Doctor lost Harry in a Somerset wood in November 1936, and found his grave in December 1936, causing him and Sarah to investigate what had happened to him. Learning that the land had been "woken up" by the spell of Hester Stanton, the Doctor and Sarah put the land back to sleep using the blood of werewolf Emmeline Neuberger before returning to November to recover Harry, after Sarah received confirmation from a dryad that they had done so. (PROSE: Wolfsbane)

Upon arrival on Earth, the Doctor, Sarah and Harry entered Scotland and met up with the Brigadier, where the group discovered that an alien race known as the Zygons were planning to use a Skarasen to attack London and abducting people to power body-prints that let them shape-shift into the forms of humans as disguises, the disappearance of the Duke of Forgill being among them. The Doctor and company had several close calls with the Zygons and eventually discovered the location of their spaceship, rescuing everyone, during which, the Doctor instigated the ship to self-destruct.

Discovering the plan was to have the Skarasen besiege Stanbridge House in a display of power, the group made haste to London. As the Brigadier and UNIT took care of the surviving Zygon commander, Broton, the Doctor found the trilanic activator used to control the Skarasen's movement and gave it to the Skarasen, who ate it and returned to Loch Ness. The Doctor prevented the destruction of the city, though the monster was still seen by the populace, and the Bridgadier would have to quietly cover up the incident. After returning to Scotland to retrieve the TARDIS and bring the Duke back home, Harry chose to leave the TARDIS and find a more conventional means of transportation, while the Doctor managed to persuade Sarah to stay. (TV: Terror of the Zygons)

The Doctor and Sarah Jane next landed on Zeta Minor, thirty-thousand years in the future. Accused of killing the crew attempting to mine the planet for alternative sources to replace their dying sun, the Doctor instead found that the planet was the boundary between the normal universe and the anti-matter universe; taking any mineral from the planet would trap a ship there. The crew's leader, Professor Sorenson, had been infected with anti-matter and was fighting off its influence as he kept changing back and forth into a monster that mummified living beings. The Doctor tricked Sorenson into the TARDIS and kicked him into the pool of anti-matter, releasing the expedition ship and restoring the professor to normal. (TV: Planet of Evil)

The Doctor and Sarah next visited London in 1666, with Sarah Jane falling victim to the Black Death. Before he could save her, the Doctor was held responsible for the Great Fire of London by Sergeant George Mullens, despite helping locals to put it out. However, he escaped a lynch mob and cured Sarah back at the TARDIS. (PROSE: The Republican's Story)

The Doctor and Sarah Jane posed as Earth delegates on the planet Farrash, a dying planet that official Earth delegates took no interest in. During a public demonstration, the Doctor was separated from Sarah Jane and became caught up in a protest against "baby killing". The Doctor learned the Leader was sanctioning the abortion of foetuses in order to supply his scientists with the neurochemicals their experiments to save Farrash required. One scientist created a mechanical body that swiftly became a rogue robot and went on a killing spree. The robot fell through the ground and became trapped underneath civilisation. With the Leader killed, the Doctor encouraged the population to work together to find a way of saving Farrash, and left with Sarah Jane. (PROSE: Rights)

Attempting to return to UNIT, the Doctor instead arrived at a priory in 1911, on the future site of UNIT headquarters. There, he had to prevent the last of the Osirans, Sutekh, from escaping his prison in Egypt and destroying the universe. Though unsuccessful in stopping Sutekh's servant, Marcus Scarman, from releasing him, the Doctor was able to delay Sutekh's trip through a time corridor to the priory by moving the corridor's threshold to the far future, thus effectively ageing him to death. Not realising his actions would cause the thermal balance to equalise, the Doctor accidentally set the priory on fire. (TV: Pyramids of Mars)

Holidaying at the ruins of Phaester Osiris with Sarah, the Doctor was kidnapped by archaeologist Edwin Carver, and stopped him and the cult of the Black Pyramid from awakening Horus. He destroyed the Black Pyramid afterwards to prevent Horus from ever returning. (PROSE: Scarab of Death)

After landing near a manor house in 1764, the Doctor nearly drowned in a frozen lake while following giant cat footprints. He was rescued by Rector Adams, and decided to remain when he and Sarah saw a 20th-century double decker bus in the woods. Adams invited them to accompany him to Lady Huntingdon's ball, where the Doctor was reunited with Iris Wildthyme and learnt the bus was actually her TARDIS. He discovered Iris intended to marry off her companion, Edwin Turner, to Lady Huntingdon's granddaughter, Bella, so that she would inherit the estate. When the Rector was killed by a giant animal, the Doctor discovered Huntingdon and Bella were actually shape shifting cat aliens who wanted to steal Iris' TARDIS. Bella turned against Huntingdon, and before Huntingdon could hijack Iris' TARDIS, the Doctor trapped her in a pocket dimension with the use of a Time Lord dimensional message capsule. Afterwards, the Doctor and Iris went their separate ways again. (PROSE: Old Flames)

Afterwards, the Doctor seemingly found himself in a town Sarah Jane had previously visited for a newspaper article. They ultimately found that it was a facsimile of the town, not even actually on Earth, populated by androids under the control of the Kraals. The Kraals' own world had become uninhabitable, leading them to plan on wiping out Earth's population with a virus, then populating the planet themselves. Discovering Sarah had been replaced by an android, the Doctor found and rescued her. With the help of Harry Sullivan and UNIT, the Doctor was able to stop the aliens and rescue the townsfolk the Kraals replaced. (TV: The Android Invasion)

Association with UNIT
After he and Sarah Jane returned to UNIT HQ, the Doctor based himself on Earth, staying at his old cottage and resuming use of Bessie, (COMIC: Death Flower, Return of the Daleks) while Sarah Jane continued working as an investigative reporter. (COMIC: The Hoaxers) However, the two frequently took trips in the TARDIS, (COMIC: The Wreckers; PROSE: A New Life) and were often accompanied by Harry. (PROSE: The Hospitality on Hankus) While working with UNIT, the Doctor started to write a series of educational books called Doctor Who Discovers. The intended title for the series was The Doctor, Who Discovers..., but the publishing company misprinted the title, resulting in the author being mistakenly credited as "Doctor Who". The Doctor completed five books in the series. He began researching the Princes in the Tower for the sixth book, Doctor Who Discovers Historical Mysteries, but left it unfinished. (AUDIO: The Kingmaker)

The Doctor and Sarah Jane investigated strange goings-on at the Vegpro factory near Suffingham. They discovered that the company's founder, Professor Sarric, was a plant-like alien planning to take over Earth with his deadly Sarricoid plants. The Doctor defeated Sarric and had all the Sarricoids destroyed. (COMIC: Death Flower)

When the TARDIS was diverted to a space station in the Milky Way, the Doctor came across an operation to build a fleet of TARDISes to conquer the galaxy, which was being mastered by the Daleks and a renegade Time Lord called Shazar. After briefly falling into a deep coma, the Doctor saved Sarah Jane from Shazar and broke his alliance with the Daleks. But Shazar later convinced the Time Lords that the Doctor had allied with the Daleks. After proving his innocence and destroying the Dalek space station, the Doctor had Shazar exiled. (COMIC: Return of the Daleks)

The Doctor next visited Saxon Britain and lost the TARDIS to the Danes and their god, Woden. Aided by the Saxons, he fought off their invasion army and regained his TARDIS. (COMIC: Woden's Warriors) The Doctor visited Neuronic space and saved his friends from Skizos. (COMIC: Neuronic Nightmare)

Wanting to make changes in the TARDIS, the Doctor constructed an Oscillating Reverberator Unit. However, he ended up transporting Sarah and Harry onto a galleon in space, where they were taken hostage by space pirates. The Doctor managed to land the TARDIS before his companions were thrown into space. (PROSE: Avast There!)

Soon after, the Doctor, Sarah, and Professor Vittorio Levi were taken prisoner on Aquatica by the Medusians, who wanted the TARDIS. Escaping, the Doctor and his two friends met the Phyllosians, the sworn enemy of the Medusian. Embroiled into a war between two kingdoms, the Doctor negotiated peace, and he and his companions decided to spend a number of months on Aquatica before returning to Earth. (PROSE: War on Aquatica)

The Doctor defeated the reptilian Zanons on Zoto in the 41st century, (PROSE: Cyclone Terror) and investigated a Time Cube called "Crystal Z" in the American desert. (PROSE: The Time Snatch)

The Doctor's body was stolen by Rascla, the twisted master of the planet Torm, who intended to unleash a virus onto Mitra B and leave its galaxy vulnerable to attack. Whilst Rascla made plans to dominate the galaxy, the Doctor had secretly taken over Sarah Jane's mind, who, along with Harry, had been hypnotised into helping Rascla. The Doctor endured a brutal psychic duel with Rascla, and Rascla's spirit was destroyed, enabling the Doctor to reclaim his body and make sure Mitra B's galaxy was protected. (COMIC: The Body Snatcher)

Intending to take Sarah and Harry to Phenolyadron, the Doctor was puzzled when the TARDIS was diverted to the planet Peugross in the 37th century. Whilst there, the Doctor, Sarah and Harry discovered a human crew from Earth had mutated into Eye-Spiders, and were commanded by the Doctor's old friend, Xerxes Periopolos. The Doctor reversed the mutation and repaired the rocket, so that the crew could return to Earth. (PROSE: The Eye-Spiders of Pergross)

The Doctor accidentally landed the TARDIS in a swamp on Diamedes, where he meet the gentle, dim-witted Slodes and saved them from swamp creatures. (PROSE: Detour to Diamedes)

During another trip into space, Sarah Jane was kidnapped by the Verulan, and the Doctor and Harry travelled to Earth, which the Verulans had planned to attack, and sought refuge at the home of Geoff Sinton and his family. The Doctor used the Sintons' TV to make contact with the Verulan war marshal, Kathnor. He tricked Kathnor into releasing Sarah, and later destroyed the Verulan ship once Sarah had escaped in the escape pod. (PROSE: The Last Broadcast) After defeating the Verulans, the Doctor and Harry were almost run over by Will Hoffman. (PROSE: The Terror of the Darkness)

On another mission for the Time Lords, the Doctor was sent to destroy a space station that held the Bendriggans' virus. However, he and Sarah were accused of murdering a messenger and sentenced to death by Admiral Cosmicon, the Bendriggan commander. The Doctor proved his innocence by sending a message in Time Lord logic to a Bendriggan code expert. But winning their trust was short-lived when many Bendriggans became infected. After watching the Admiral die, the Doctor set the Bendriggan flagship on collision course with the space station, destroying them both and saving the remainder of the Bendriggan race. (COMIC: Virus)

The Doctor next found his TARDIS forced to land on Karn by the Time Lords, as the Sisterhood of Karn had been crashing ships that passed Karn to protect what was left of their Elixir of Life. The Doctor used a firecracker to unplug the crevice the elixir came from, being promptly booted out. He then discovered the evil Time Lord Morbius was being resurrected in a patchwork body. Defeating him in battle of mindbending, the Doctor managed to reduce Morbius to a mindless beast that tumbled off a cliff to his death. However, the Doctor was left severely drained, but the Sisterhood allowed him to drink some their elixir, which restored the Doctor's health. (TV: The Brain of Morbius)

The Doctor and Sarah took a brief trip to 1930s Chicago to acquire a new fluid link for the TARDIS. (PROSE: The Duke of Dominoes)

At Sarah Jane's request, the Doctor posed as a hostile alien to teach Hiram Lutz a lesson when he refused to donate money for a struggling disabled children's home. (COMIC: The Hoaxers)

Attending another UNIT Christmas party, the Doctor was unable to prevent a Voddod ship from crashing to Earth. Aided by Sarah Jane and Harry, the Doctor raced to find Brac, the crashed alien warrior, before UNIT troops found and killed him. (PROSE: UNIT Christmas Parties: Ships That Pass)

The Doctor investigated an abandoned lighthouse in North Cornwall and discovered a gigantic lizard had been killing the local villagers. With no other option, the Doctor was forced to use a naval rocket to destroy it. (COMIC: The Tansbury Experiment)

The Doctor next took Sarah to the circus to watch a performance by the great P. T. Barnum. However, they lost the TARDIS to circus performer Benjamin, who planned to use the time machine as a new magic act called "the Wondrous Box", accidentally transporting the time machine back to various points in the circus's past. The Doctor managed to bring Benjamin to the present, and regained his ship. (AUDIO: The Wondrous Box)

Being summoned by UNIT on behalf of the World Ecology Bureau, the Doctor saw pictures of a pod discovered in Antarctica. The Doctor and Sarah were flown to Antarctica, and found that the pod was Krynoid and had infected Charles Winlett. Outside, they also found another pod, and put it in the freezer. Before they could do anything for Winlett, he mutated further and became aggressive, going on a rampage. While trying to stop the new Krynoid, the Doctor failed to stop Scorby and Keeler, who worked for Harrison Chase, from finding the other pod, and escaping with it.

After the Krynoid was destroyed by Scorby's bomb, the Doctor and Sarah were rescued, and brought back to England. Investigating Chase Manor, the Doctor and Sarah encountered the Krynoid, who had infected Keeler, and had taken control of the body of Harrison Chase, planning to spread its seeds to take over Earth. While fighting Chase, the Krynoid and the plants animated by the creature, the Doctor called in UNIT, who worked with the RAF to destroy the Krynoid and the manor along with it. (TV: The Seeds of Doom)

After a trip to Hollywood, (COMIC: Unnatural Selection) the Doctor and Sarah visited St Cedd's College in 1955, where they encountered Professor Chronotis. During this meeting, the Doctor recommended that Chronotis read The Time Machine. (PROSE: Cambridge Previsited) They were also sighted at the UNIT Research Institute by the Brigadier's seven-year-old daughter, Kate. (PROSE: The Day of the Doctor)

Arriving in 1998 London, the Doctor became involved with stopping the Voracians from using a computer virus that would make all technology sentient and rise up against humanity. He destroyed the virus and chased them off the planet. (PROSE: System Shock)

Final adventures with Sarah
The Doctor and Sarah visited London to find that the Pescatons were invading Earth. The Doctor discovered their weakness to high-pitched noise and set a trap for their leader, Zor, killing him. When he died, all the other Pescatons died as well. (AUDIO: Doctor Who and the Pescatons)

On Vona, the Doctor joined forces with his old friend, Olak, to break peace between two robotic armies, the Domos and the Yenge. (COMIC: The Rival Robots)

During a trip in space, the Doctor accidentally brought the Helix Intelligence to San Martino, Italy, in the 15th century, where it planned to dominate the human race by using the Brotherhood of Demnos as its agents. Because the agents had been converted into pure energy beings by the Helix, the Doctor tricked the Brotherhood's leader, Hieronymous, into using all his energy until he vanished. Using his mask and cloak, the Doctor posed as him and used a device to drain the energy out of the rest of the Brotherhood, killing them and saving the Earth. (TV: The Masque of Mandragora)

Soon after, the Doctor rescued Piram, the lone survivor of a Lizardian space pirate attack and helped him take revenge on Skarnus, destroying a barren moon that he had turned into his base. (COMIC: Jackals of Space) On Calderon IV, the Doctor became the target of a revenge attack by a bitter old man whom he opposed in his previous incarnation. (PROSE: The Android Maker of Calderon IV)

The Doctor and Sarah spent nine weeks travelling to the beaches of Geshtinanna. During this time, they became trapped inside a "ghost TARDIS" which was travelling on a parallel course to their TARDIS. (PROSE: Eternity)

Whilst Christmas shopping in 1980s New Zealand, Sarah and many other shoppers were kidnapped, along with a large percentage of turkeys. Investigating, the Doctor discovered the Hazoodians were using turkeys to make alcohol. Realising the humans were being kidnapped by accident, the Doctor returned them to Earth. (PROSE: Autaia Pipipi Pia)

Receiving another summoning from the Brigadier, the Doctor was forced to assist UNIT by investigating alien activities in the Channel Island. (PROSE: Hello Goodbye)

The TARDIS' steering went out, causing the ship to go back in time forty-five-hundred-million years. The Doctor and Sarah observed Earth, at the time a mass of molten rock, develop into a world with an atmosphere and life. They also encountered Megron, a Lord of Chaos claiming to be ruler of Earth until the Doctor banished him. (AUDIO: Exploration Earth: The Time Machine)

The Doctor made another visit to Vortis, where he found the crystalline Clynex was draining the energy from its surroundings and attracting the Menoptera to their deaths. The Doctor saved them from Clynex by shattering it with his sonic screwdriver. (COMIC: The Naked Flame)

The TARDIS landed in an English quarry, where it was buried by an explosion. The Doctor emerged unscathed, but Sarah was taken ill and so he accompanied her to hospital. There, he discovered she had come into contact with a stone hand and, when Sarah stole the hand and fled, followed her to Nunton Experimental Complex. Her wearing of a ring brought her under the control of Eldrad, a Kastrian scientist. The Doctor used a cooling duct to reach Sarah and brought her to her senses.

Eldrad restored herself using the reactor core. The Doctor agreed to take her back to Kastria, her homeworld, but only in the present, not her home time, as this broke the Laws of Time. On Kastria, Eldrad was injured by an acid-laden booby trap, so the Doctor and Sarah had to conduct her to a regenerator chamber. There she was restored to her male form. Eldrad discovered his people to be dead and asked the Doctor to return him to Earth so he could rule over humanity. Fleeing from him, the Doctor made use of his scarf, with Sarah holding the other end, to trip Eldrad, who fell into an abyss.

Back in his TARDIS, the Doctor received a telepathic summons from Gallifrey and was forced to leave Sarah behind, just as she herself had decided to return home. They both agreed they wouldn't forget one another as Sarah left, (TV: The Hand of Fear) but the Doctor had accidently left her in Aberdeen, Scotland instead of South Croydon. (TV: School Reunion)

Return to Gallifrey
Discovering that the signal hadn't come from someone he knew, the Doctor returned to Gallifrey, just as it was the time of the election for Lord President, and theorised that the departing President was in danger. Stealing a robe to blend in, the Doctor attempted to prevent an assassination, but ended up framed for murdering the Lord President. To keep himself from being executed, the Doctor declared his own candidacy for Lord President. Believing the Matrix would give him clues as to who was behind this, the Doctor ended up in a mental duel with the culprit.

After finding the assassin, the Doctor learned that it was Goth, another Lord President candidate, who was being manipulated by ; since their last meeting, the Master, with no regenerations left, had degenerated into a rotting corpse. The Master was plotting to use the Eye of Harmony in an attempt to restart his cycle of regenerations by using the Sash of Rassilon to protect himself from the effects of the Black hole that would destroy Gallifrey as a side-effect.

After failing to convince the Master that, since the sash was damaged in the death of the old president, it would put the Master at risk, the Doctor fought him off. Though the Master managed to escape capture, the Doctor left his former teacher, Borusa, to lead Gallifrey as Cardinal, (TV: The Deadly Assassin) though, as the only candidate left, he was still eligible to gain the title of Lord President, even after leaving. (TV: The Invasion of Time)

Companionless travels
Now on his own, the Doctor landed on the Queen Mary in 1963, during a voyage from Southampton to New York City. He discovered physicist Peter Osbourne had built a time visualiser prototype that was sending ripples backwards and forwards in time, capturing the fragmentary essences of people in the moments of their worst despair. The Doctor destroyed the machine, but the gestalt of spirits remained bound to the ship, with Osbourne included in their number. (PROSE: Ghost Ship)

The Doctor decided not to return for Sarah Jane, fearing he would have to watch her grow old and die. (TV: School Reunion) However, he did visit her to apologies for the way they parted company and to say a proper goodbye, quickly departing afterwards to protect her from any further heartbreak. (PROSE: Farewells)

Arriving in 1990s Tokyo on Christmas Eve, the Doctor celebrated Christmas in the Emperor's Garden with a member of the Divine, an ancient shapeshifter. (PROSE: Ode to Joy)

The Doctor later attempted to form a band with his three predecessors, but creative differences, and the fact that they all wanted to play the drums, broke them up. (COMIC: Day of the Tune)

The Doctor incurred the wrath of Droge of Gabrielides, who "offered an entire star system for [his] head", (TV: The Sun Makers) and also refused to answer a summons from his first incarnation. (PROSE: Five Card Draw)

Wanting to learn first-hand about history, the Doctor became a taxi driver in London and met architect James Willaker and took him to dinner. He told James about his travels in time, and James inspired him to travel to the building the architect was then working on; Chase Manor. (PROSE: Only Connect)

The Doctor was caught in the destruction of a cemetery in an earthquake, but was saved by Ana Maria Carla Perez de Calixtro. After spending Christmas with her family, the Doctor travelled forty years into the future, and met Ana when she was an old lady so he could take her back in time every Christmas to visit her father's grave. (PROSE: Callahuanca)

On another mission for the Time Lords, the Doctor was joined by a Craxon called Andric to find a new source of Diloona and they faced a number of perils on a satellite at the hands of the Managans. (COMIC: The False Planet) He next helped Inspector Keel defeat the Zandans, beings that fed on fire, by pouring soot on them and neutralising their heat cells, (COMIC: The Fire Feeders) and forged a truce between the Braggens and their rulers the Kling on Earthos by unmasking the Kling's Emperor as a computer. (COMIC: Kling Dynasty)

Captured by the Master
The Doctor, along with his six other incarnations, was trapped in the Determinant by, but he was able to create an amorphous being named the Graak to save him and his other selves. The Doctor instructed the Graak to start his mission by finding a radio transmitter in the Third Doctor's laboratory to contact the Brigadier.

After the Graak freed his predecessors, the Doctor began pleading with him to save him, as he was in danger of being "swept away" into an "infinite of nothingness". Later, the Doctor informed the Graak to only enter the Determinant when he was "mentally prepared", as failing the challenge would result in certain death, and instructed him to go to the Zygon chamber to retrieve a Skarasen calling device.

When the Master and the Graak battled in his brain, the Doctor helped the Graak by navigating him around and giving details on the adversaries he encountered. After the Graak defeated the Master, the Doctor was finally freed when the Graak sacrificed its life force to liberate the trapped Doctors. (GAME: Destiny of the Doctors)

Skirmish on Aprilia III
The Doctor arrived on Aprilia III in a parallel dimension, where he met Captain James T. Kirk, Spock, Dr. Leonard McCoy and Scotty. The group had been looking for a lost archaeological team, and had discovered the base. The Doctor offered them jelly babies and used his sonic screwdriver to break the lock the group had been trying to open.

They discovered the researchers standing catatonically, with small cybernetic devices in their ears. Dr. McCoy began to remove the devices and revive the crew, but was interrupted by the arrival of a Cyber-Leader and two Cybermen. A firefight ensued, but the Starfleet phasers were ineffective against the Cybermen. The Doctor used the gold cover from Kirk's communicator to clog the Cybermen's respiration. After the Cybermen were defeated, the Doctor slipped away quietly. (COMIC: Assimilation²)

Old friends
The Doctor travelled to 16th century America and was hailed as a god by Taric, high priest of the Mandrans, (COMIC: The Sky Warrior) visited William Shakespeare after he had sprained his wrist to help him draft Hamlet, (PROSE: The Stranger, The Writer, His Wife and the Mixed Metaphor) and became trapped in a dreamscape with a servant of the "Master of the Blackhole", which nearly destroyed his mind completely. (PROSE: Master of the Blackhole) He later made several notes about the updates made to Hamlet's soliloquy. (PROSE: Hamlet's Soliloquy)

The Doctor accidentally awoke an army of Sea Devils, who launched an attack on a submarine in England. However, before the Doctor could move against them, he unexpectedly encountered the Third Doctor. Adopting a new identity to protect the timelines, the Doctor helped his previous incarnation to defeat the Sea Devils, and made a quick exit before his third incarnation could discover who he was. (COMIC: Under Pressure)

Soon after, the Doctor reunited with former companion, Liz Shaw. They had dinner and the Doctor took her aboard the TARDIS, and the pair travelled together for a short period of time. (PROSE: Down to Earth)

Summoned to Earth by Brigadier-Lethbridge Stewart's recall device, the Doctor discovered UNIT was facing closure and the pair attended a court hearing in New York to save the organisation, but the Doctor was side-tracked when he discovered the Brigadier did not summon him to Earth. Investigating led him to the Museum of Art, and he was soon held at gunpoint by Robin Oemington, a former spy who blamed the Doctor for the downfall of his career. Robin was killed by police before he could kill the Doctor. However, the Doctor discovered Robin had constructed a bomb capable of blowing up the solar system, and that the deceased spy planned to frame him. The Doctor managed to defuse the bomb at the last moment and successfully secured a bright future for UNIT and the Brigadier. (PROSE: UNITed We Fall)

The Doctor worked alongside Harry Sullivan again to return a peaceful alien home and to also protect it from a ruthless UNIT colonel named Dennis Horsely, who believed that the creature should be killed and experimented on, (PROSE: Mutiny) and attended the funeral of Alistair Gordon Lethbridge-Stewart with all of his other incarnations. (PROSE: The Gift, Shroud of Sorrow)

The Doctor spent a long period of time tracking down Jessica Willamy, who he had met in his second incarnation. He discovered she had been a fugitive for forty years, ever since their last meeting and he saved her from an assassin in New England. (PROSE: Wonderland)

During a visit to London in 1999, the Doctor worked with Harry Sullivan to deal with a new group of Voracians, who had infiltrated the British Government. Unlike the direct military action of the first group that the Doctor had encountered, these Voracians intended to manipulate the government into dismantling the British military by staging a coup and shutting down the army in the aftermath, telling the government that the goal was to divert money into education and medicinal programs when in reality they would use the opportunity to distribute Voractyll-programmed technology more effectively while disguising it as anti-Millennium-Bug software. Having exposed the coup, the Doctor and Harry tracked down the Voracians before they could activate Voractyll, distracting them long enough for the Doctor to infect their own software with the Millennium Bug, causing Voractyll to shut down when it passed through them. (PROSE: Millennium Shock)

The Doctor attended Clio's fifth birthday party, and bought her a bag of jelly babies as a present, (PROSE: The Glass Princess) and watched Leonardo da Vinci paint the Mona Lisa, thinking the model was a "dreadful woman with no eyebrows who wouldn't sit still". (TV: City of Death) Posing as a Punch and Judy man whilst hunting Cybermats in 1879, the Doctor met Winston Churchill. (PROSE: The Lost Diaries of Winston Spencer Churchill)

Temporary companions
Still travelling alone, the Doctor gained a companion in Miss Young, and the pair went to Scotland in Bessie to meet with Professor McBane, an old friend of the Doctor who had summoned him. McBane revealed that a meteor had crash landed in oil rig waters, and he wanted the Doctor's input on the chance of alien hostility. As the group flew over the area in a helicopter, giant tentacles arose from the sea and began attacking a local ship. The Doctor was able to take a sample of the pink substance from the creature back to the laboratory, where he discovered that it was seaweed contaminated from radiation from deep space brought by the meteorite. Furthermore, the mutated seaweed was attracted to sound, so the sound of the oil rig put it in danger.

The Doctor and Miss Young headed out on a boat, using a sound-emitting gadget to attract the mutated seaweed. A tentacle grabbed the Doctor, but Miss Young cut it off. They lured the mutation into a shallow bay where it couldn't dive and dropped drums of petrol from the boat. After they were flown out of the area, the petrol was lit on fire, killing the beast. Afterwards, the Doctor and Miss Young drove back to the TARDIS for more adventures. (COMIC: The Sea Devil)

The Doctor went to Xenon, where he picked up Milena from the planet. In return for a favour, Milena's father had asked the Doctor to take his daughter on an adventure. The pair went on a mostly peaceful trip, until they were forced to land on an asteroid. There, Milena was possessed by a species known as the Zicons. The Doctor was eventually able to trick them out of her body, and safely dropped her back on her home world. (PROSE: Milena)

New acquaintances
While tracing a historical anomaly, the Doctor met Nyssa, a future companion of his, who travelled back in time with him when she learned that he was going into the past to investigate Roger Bacon, who had been erased as a result of the anomaly that the Doctor was trying to track, Nyssa seeking a time of peace after the chaos of her present. Although their investigations revealed that Bacon's assistant was trying to help him create an elixir of life, the Doctor and Nyssa never learned the reason for this anomaly, their time together ending with the Doctor taking Nyssa back to her time while aware that he would have to take care of the younger Nyssa when she became his companion in the future to avoid causing a paradox. (PROSE: Asylum)

Going undercover at the construction of the Northern Line in 1930s London, the Doctor met Nicholas Clement and located an alien anomaly known as "Kappa 12" under Alexander Palace station. Aided by Nicholas, the Doctor stopped Kappa 12 and a trans-dimensional organisation called "The Union" from destroying Earth, Alpha and Temporalities Beta. (PROSE: The Northern Heights)

The Doctor was recruited by Charles Leyton, director of the Greater European Union's Intelligence Ministry, to investigate media mongul James Baron. On his mission, the Doctor was paired with Susan King, Baron's old flame. The pair discovered Baron had been smuggling weapons into the country and went undercover at Baron's Enterprises. After foiling his plan to seize control of Britain, the Doctor was held at gunpoint by the unhinged Baron, which forced Susan to shoot Baron before he could kill the Doctor. (PROSE: The Baron Wastes)

Alongside a 1939 thief called Jacob Abiathar Earl-Thornton, the Doctor visited Earth in the year 50 million, where they encountered two warring species of robot ants. (PROSE: Earth) The Doctor next tracked down an object that could bring machines, such as vending machines, to life, assisted by a younger woman. (PROSE: My Hero)

The Doctor checked into a London hotel in 1910 and befriended a lift operator, Philip Fowler, who spoke of the King's death and had dark predictions of the future. Investigating, the Doctor discovered Fowler was an alien device to precipitate a revolution on Earth. (PROSE: In Case of Emergencies)

Visiting the wizarding land of Samarkand, the Doctor rescued Al Urd-Din from the pit, causing Al to assume that the Doctor was a magical being. The Doctor discovered the evil Vizier was plotting to marry Al's lover, and trapped him in a World of Shadows. (PROSE: The Nobility of Faith)

First adventures with Leela
The Doctor returned to the planet colonised by the Mordee expedition centuries before, where he found that he was remembered as an evil god called "the Evil One" by the descendants of the colonists. Descendants of the colonist's survey team had become a warrior tribe called the Sevateem, while descendants of the technicians had become a technologically advanced tribe called the Tesh. Infiltrating the "Sacred Heart" of the old Mordee expedition ship with the help of one of the Sevateem, Leela, the Doctor cured the computer Xoanon of his multiple personalities. Leela, wanting to come with the Doctor, forced her way into the TARDIS, becoming his new companion. (TV: The Face of Evil)

The Doctor and Leela uncovered experiments into telepathy undertaken by several university students, which threatened a weakness in the multiverse that was in close proximity, made even worse by a university professor's attempt to create a flawed time machine to undo an event in his past when he beat his daughter to death during an argument. However, due to the interventions of the TARDIS, the damage to the multiverse was repaired, but, as a result, the timeline was replaced by one where the professor reported his crime rather than hiding it. The Doctor noted that he and Leela would forget about the whole affair when they stepped out of the TARDIS, as none of the people they encountered or events they witnessed would have ever existed. (PROSE: Psi-ence Fiction)

On a Sandminer in the 23rd century, the Doctor and Leela were accused of killing members of the crew, and taken prisoner. They later discovered a madman named Taren Capel was murdering the crew, hoping to help his robot "brethren" rule humanity. However, the Doctor turned Capel's reprogramming of the robots against him by using helium gas to make his voice unrecognisable to them, leading to his death. (TV: The Robots of Death)

The Doctor received a summons from the Brigadier to investigate a strange object in Scotland, which he traced to one of the islands in Shetland. While the TARDIS' file on the island identified it as being uninhabited, the Doctor was attacked by Davy McTavit and Murdo Jamieson for being an "offlander", until Joanna Renwick stopped them. Learning that Leela had experienced something whilst rowing, the Doctor theorised that the lights in the sky were not a natural phenomenon, just as Viking artefacts started to attack Joanna. After falling down a hole while trying to find Angus Renwick, the Doctor was attacked by something in Viking armour, but he found his way onto Nardos' ship. After helping Leela to escape the flames, he and Leela travelled back in time accidentally and saw Angus' father during his mission in the Second World War. The Doctor worked out that the ship's defences were causing time to fracture. He was given the "wolf's eye" from a young Angus and used it to go back to the future, and tried to convince Nardos to stop his plans as it would destroy humanity. (AUDIO: The Helm of Awe)

Educating Leela
The Doctor brought Leela to Victorian London and the pair encountered the magician Li H'sen Chang and his master, the self-styled Weng-Chiang, who was actually the 51st century criminal Magnus Greel. With the help of Henry Gordon Jago and Professor George Litefoot, the Doctor was able to stop Greel from using a failed time machine that would have destroyed reality, but when the attempt happened without a crucial part, Greel was caught in an explosion. (TV: The Talons of Weng-Chiang)

After saying goodbye to Jago and Litefoot, the Doctor followed a distress signal that took him and Leela to a country house in Kent in 1895. At the house, the Doctor had to stop Leela from attacking the butler, Jenkins, and told him that his master, Lord Jack Corrigan, had taken a spaceship. After the TARDIS departed, the Doctor traced it to the Nerva Beacon centuries in the future. They landed on the Chandler and joined its crew pretending to be part of its construction crew for the Nerva Beacon. Shortly after boarding the Nerva Beacon, they were arrested by a Drudger and taken to Giles Moreau where he questioned Henry McMullan about the stolen spaceship.

The Doctor worked out that Henry was spreading an infection among the people on the Nerva Beacon. After Jim Hooley became ill with the infection, the Doctor stopped Alison Foster from touching him. He managed to get them back onto supply ship to get a message to quarantine the Nerva Beacon. Shortly afterwards, the Drellerans showed the Doctor that they infected Jack and his colleagues because of Jack's subjugation of their people. He convinced the Drellerans with the help of Alison to give them the vaccine to the stop the infection spreading and cure those with the disease. (AUDIO: Destination: Nerva)

Deciding that he should take Leela to see her ancestors, the Doctor took her to Roman Britain in 60 AD. Shortly after arriving, they met Boudica when she was being attacked by Festucas and Pacquolas. He was appalled when Boudica killed Pacquolas after he had surrendered. When he told her of Boudica's fate, Leela wanted to change her fate, but the Doctor tried to dissuade her from altering history. He tried to escape back to the TARDIS, but was captured and imprisoned with Bragnar. Boudica knew that threatening Bragnar would cause the Doctor to tell her the future. He managed to escape and rode to Boudica's battle to save Leela from being killed. (AUDIO: The Wrath of the Iceni)

Intending to take Leela to 2015, the Doctor accidentally landed in London in 2025, and noticed a set of anachronistic energy readings coming from the National Museum. He allied with protester Jack Coulson to destroy GlobeSphere Corporation because of their plans to exploit their consumers. Investigating their headquarters, the Doctor discovered that the company had been infiltrated by the Daleks, and that the energy readings were associated with a Dalek Time Ship. He rescued Leela from being converted into a Roboman.

Using the Robotisation mechanism, the Doctor got information from a Dalek that they wanted the energy for their plans and headed for the Moon. He worked out that Damien Stephens was a high functioning Roboman, and also found out that the Daleks were plotting to force the Moon out of Earth's orbit, so that it would cause highly destructive floods and tectonic events that would ultimately engulf the human race. However, the Doctor once again stopped the Daleks by funnelling all the power through their ship. (AUDIO: Energy of the Daleks)

The Doctor took Leela on holiday on the planet Shontaa, where they battled two Zygons who were engaged in a bitter feud. (COMIC: Rest and Re-Creation) The Doctor and Leela also got lost on Riftan Five for three days, (COMIC: Timeliney Wimey) and then visited Bob Dovie at 59A Barnsfield Crescent in Totton, Hampshire on 23 November 1963. (AUDIO: The Light at the End)

Planning to visit Bexhill on Sea, the Doctor landed the TARDIS near Sissenden Village in 1588, and distracted William Redcliffe so that D'Arcy could escape. He later saved Pincham from being killed as a witch. He met with Nicholas Harney and went with him home to London to rescue D'Arcy from being tortured by Redcliffe. There, he encountered Vituperon who, posing as the Devil, teased him in the delirium. The Doctor was then imprisoned in the Tower of London, but he escaped after being taken to the gallows, having worked out that the imps were copies of Vituperon. After the defeat of the Spanish Armarda, he went back to use the TARDIS to defeat the Vituperon. He went into their lair, with Leela as his anchor, and sealed Vituperon in his realm. (AUDIO: The Devil's Armada)

The Doctor next visited Joshua Douglas and his family, where he re-encountered the imprisoned emperor of the Z'nai, whom he had contained long ago. The Emperor hoped to find an antidote for the plague which Douglas had released to destroy his people. Douglas' daughter freed the Emperor, sparking a resurgence of the Z'nai Empire. For an unknown reason, Leela became the virus' vector, infecting the Z'nai with it. She wiped out the Z'nai except for the Emperor, whom the Doctor imprisoned again. (AUDIO: The Catalyst)

After the TARDIS malfunctioned, the Doctor and Leela found themselves on the tranquil planet of Synchronis, where they planned to relax until the Doctor was attacked and left in a coma, leaving Leela to fend for herself. When he recovered, the Doctor managed to sabotage the ongoing Empathy Games in which Leela was a participant and restructure the society. (AUDIO: Empathy Games)

The Doctor spent a few days in New York in 1856, discussing philosophy and literature with intelligent men. Preparing to leave, the Doctor was persuaded by Leela to attend a séance conducted by the Fox sisters, who summoned the spirit of Neeva, the Sevateem's shaman. (PROSE: Shamans)

When the Time Lords sent him and Leela to Dowcra, the Doctor was captured by Reaver and sent to work with the rest of the prisoners of the Sontarans, working on the clone vats, where he learnt more about the Sontaran invasion from Irving. When he learnt of the human experiment to create a method of instantaneous travel which would be deadly in the hands of the Sontarans, the Doctor thought this was why the Time Lords had sent him to Dowca. He tried to assassinate Strang by using the probic vent, but it didn't work, and the Doctor was sent to help Rosato to complete the portal he was creating. He tried to convince Rosato that wiping out the Sontarans would let the Rutan Host swarm, but his subconscious betrayed him and he accidentally gave Rosato the equations to complete the portal. Because the Doctor wasn't certain that he could make the Sontaran clones good, Leela destroyed all the vats, much to the Doctor's disapproval. (AUDIO: The King of Sontar) He spent two days contemplating Leela's actions, before realising that she only did the Time Lords' bidding. (AUDIO: White Ghosts)

Continued travels with Leela
At a lighthouse on Fang Rock, the Doctor and Leela discovered a Rutan Host who was planning to make use of the Earth's strategic placement in its race's war with the Sontarans. After all but he and Leela were killed by it, the Doctor destroyed the Rutan by blowing up the lighthouse. (TV: Horror of Fang Rock)

The Doctor and Leela next found themselves on a cyber-frontier world, encountering an army of half-converted Cybermen. Originally planning to help them retrieve a weapon to destroy invading Cybermen, the Doctor sent Leela to gather a resistance and gave the half-converted their emotions back. Colonel Joshua committed suicide after seeing what he had become, whilst the rest dedicated their lives to protecting the planet. (PROSE: One Bad Apple)

Adopting K9
The Doctor, having become the host of the Nucleus, travelled to the Bi-Al Foundation medical centre in the year 5000, where its Swarm spread further, infecting numerous others. The Nucleus brought itself out of the Doctor's body and into the macro world to hatch more offspring. The Doctor travelled to Titan Base, where a hive of Swarm lay. The Doctor mixed the oxygen canisters with the methane atmosphere of Titan, blowing up the base and killing the Swarm. While there, he brought along Professor Marius' robot dog, K9, to fight the Swarm-infected humans. Unable to return to Earth with K9, Marius gave K9 to the Doctor as a gift. (TV: The Invisible Enemy)

Whilst fishing on the terraforming Mars, the Doctor, Leela and K9 became caught in a terrorist attack, and the Doctor was mistaken for the leader of the Crimson Dawn, an eco-terrorist organisation. He discovered another organisation, Redpeace, had been working with a lone Ice Warrior to restore the Ice Warriors. After dealing with the rival organisations, the Doctor awoke the cryogenically frozen Ice Warriors on the moon of Phobos and restored the planet to their control. (PROSE: Crimson Dawn)

The Doctor traced the source of a time hole to a group of scientists experimenting on a mysterious skull called Eustace. Much to his horror, the Doctor discovered "Eustace" was actually the skull of a Golden Core, responsible for creating humanity's darker side. Believing it could give them the power to rule the world, a cult used the scientist Thea Ransome as a medium for "Eustace". The cult's plan backfired, as the core simply began transforming them into Fendahl. The cult's leader, Maximillian Stael, committed suicide, preventing them from reaching the quota of thirteen Fendahl. The Doctor blew up their base, killing the transformed humans. (TV: Image of the Fendahl) The Doctor then attempted to destroy the Fendahl skull by firing it into the Canthares supernova. (AUDIO: The Dalek Trap)

Searching for a second Fendahl skull, the Doctor interrupted the first performance of Hamlet and prevented Lord Grathnave of the Erstwhile Collision from obtaining the skull. (PROSE: Hamlet)

Returning to Prague in the 23rd century, the Doctor discovered a race of super-evolving dogs had taken over the city. Taken prisoner, the Doctor, Leela and K9 befriended Ben. Together with the citizens of Prague, they staged a rebellion against the dogs and rebuilt Prague to its former glory. (PROSE: The Dogs of War)

Arriving at Megropolis One on Pluto in the far future, the Doctor learned of the Company responsible for over-taxing the populace. He then discovered that Ursurians had previously helped humanity move to Mars and then to Pluto for resources, but planned to leave them behind once Pluto was drained. He overthrew their representative, the Collector, trapping him in a jar in his true form of "seaweed", and set up a better economy. (TV: The Sun Makers)

Taking a homesick Leela to the Heligan Structure, the Doctor found himself on trial for a crime a future incarnation of himself had done to the colonists of the Heligan. However, Chairman Ratisbon insisted on a summary execution, just as the Heligan began manifesting "mobile spores" that attacked the colonists. Realising things were being triggered by an outside source, the Doctor ventured into the Heligan's root ball, and discovered that Director Sprawn had merged with the Heligan to ensure his revenge on the Doctor. Reverting Sprawn's altercations to the Heligan's spores to prune Sprawn out of the Heligan's systems, the Doctor told the colonists that a nearby world would be habitable in ten years and that they should advertise the Heligan Structure as a wonder of the galaxy. (PROSE: The Roots of Evil)

Arriving on E9874, the Doctor met with Trexa when she barged into the TARDIS. Whle meeting the Tarl leader Ergu with Calura and Gethal, the Doctor learned that the Exxilons were creating various complex constructions that would turn multiple other worlds into little more than conduits to power their primary great city, and was asked to share his wisdom with Ergu. They worked out that the Exxilon city used the minds of other races to power itself and that it turned on them in the end. With K9 to disrupt the carvings on the current construct, the Doctor was able to drive the Exxilons away from E9874. (AUDIO: The Exxilons)

The Doctor arrived on Agratis to see the Jewel of Fawton and eat a banquet. However, the Jewel had gone missing, and the Judoon had been called in to reclaim it. The Doctor went with his old friend, Provost Mason Vox, and Curator Frez to find Roget, who was suspected of taking the Jewel, while Leela and K9 distracted the Judoon. In the caverns of the Krytuk Valleys, where the Jewel was first discovered, the group discovered Roget. He had placed the Jewel, which was the hive mind for the native crystalline species, in its original place, and awoke the creatures. With the Jewel back with its rightful owners, the Judoon's search was called off. While Leela was feasting with the Judoon, Adam Mitchell kidnapped Leela and K9. (COMIC: A Rare Gem)

Reaching the edge of the universe, the Doctor met a species the Time Lords helped evolve, whose destruction of their own planet because of their advancement in evolution led to the Time Lords' non-interference policy. He helped them locate and rescue fellow descendants of their species, taking them a new planet where they could start a better life. While helping them, the Doctor battled against the Oracle, a machine that enslaved the secondary descendants with the aid of robots. (TV: Underworld)

Noticing the unreliability of K9, the Doctor and Leela acquired the parts for K9 Mark II. When Leela landed on Westtropi III, the Doctor kept fading out of time, due to the presence of the Time Vampire, which he thought had come into being due to his close proximity of his third incarnation. (AUDIO: The Time Vampire)

Lord President of Gallifrey
Returning once more to Gallifrey, and posing as vainglorious and power-mad, the Doctor sought and attained the office of Lord President from Borusa, who he had left in charge on his previous visit, as part of a scheme to save his home world from an invasion force of the Vardans. During his plan, he had Leela exiled from the Citadel so that she would gather a resistance force. He repelled the Vardans after successfully tricking them, and killed an advance party of Sontarans through traps he set for them when they infiltrated his TARDIS.

With his homeworld protected and Borusa once again in charge, the Doctor planned to resume his travels. But he learned Leela had fallen in love with a Gallifreyan guard named Andred and wished to remain with him; K9 likewise wished to stay with his "mistress". Though he seemed sad at first to lose both companions, the Doctor quickly pulled out a crate marked "K9 Mark II" from a storage area and grinned to himself. (TV: The Invasion of Time)

While he was connected to the Matrix, the Doctor gained knowledge of the Timewyrm. Realising he would forget this information, he left a time-delayed message in the TARDIS for himself as a warning. (PROSE: Timewyrm: Genesys)

Nest Cottage
Before building K9 MKII, the Doctor took up sojourn in a cottage in Sussex called Nest Cottage in the 21st century.

The Doctor began to investigate a string of murders that were caused by stuffed animals. The animals came from a taxidermy factory, run by a passionate taxidermist called Percy Noggins. Upon meeting the Doctor, Percy sent a small army of stuffed animals to kill him, since he had deemed him a threat. The Doctor discovered the stuffed animals and Percy were being controlled by the Hornets, an alien race that wanted to take control of the Doctor's mind. The Doctor lured all the Hornets towards Nest Cottage, where the TARDIS' dimensional stabilisers put up a force shield to prevent them getting out and taking over the world. (AUDIO: The Stuff of Nightmares)

The Doctor later travelled to 1932 Cromer to investigate previous incursions of the Hornets on Earth, where he found a dancer called Ernestina Stott stealing some ballet shoes with the remains of feet inside them, owned by Mrs. Fenella Wibbsey, curatress of the Cromer museum, both under the influence of the Hornets. Upon discovering the significance of the ballet shoes in his investigations, the Doctor learned they were the ballet shoes of a dancer called Francesca, just like Ernestina, and they were being used by the Hornets as a hive for their dormant swarm, which Mrs Wibbsey had been taking care of for years. The Hornets attempted to use Mrs. Wibbsey to shrink the Doctor and Ernestina down, putting them inside a doll's house filled with deadly dolls animated by the Hornets, but the Doctor escaped and found a way to bring them back to normal.

After that, the Hornets tried to occupy Ernestina's body, making her their new hive, but the Doctor stopped them by removing the ballet shoes before they could take full possession of her. He confiscated the doll's house and the ballet shoes and placed Mrs Wibbsey under his protection in Nest Cottage as his housekeeper and regularly mesmerised her to prevent the Hornets from taking over her mind. (AUDIO: The Dead Shoes) However, the Doctor later discovered that Ernestina was still carrying the dormant Hornets inside her, who then made contact with her grandson, Percy Noggins, the taxidermist who cooperated with the Hornets in their scheme to control stuffed animals. (AUDIO: A Sting in the Tale)

The Doctor then travelled to 1832 Blandford to investigate the Circus of Delights, whose arrival coincided with disappearances in the village. During this trip to Blandford, the Doctor encountered a girl named Sally, whose father had prevented her from attending. He met Dr Adam Farrow, whose sister Francesca had run away with the Circus of Delights. Sally and Farrow accompanied the Doctor in his investigation of the circus, where the Doctor discovered that the Hornets were responsible for odd goings-on at the circus, led by the dwarf ringmaster, Antonio. It was discovered that the Hornets had been taking possession of members of the village, so they could feed off the negative emotions that the villagers produced, using the circus to draw more victims into their trap. Upon mesmerising Antonio, the Doctor found out that he had come into contact with the Hornets as a young boy, in Venice, 1768 when they came out of a blue box that had appeared from nowhere.

However, after the Doctor had extracted all the information he wanted from Antonio, the Hornets had completely left his body with the intent of making Francesca their new hive. The Doctor attempted to stop the Hornets occupying Francesca, but was unsuccessful, leading Francesca to cast herself off the high wire upon the command of her masters, killing her. After the Doctor's defeat of the Hornets in Blandford, the Doctor had taken the husk of Antonio back to Nest Cottage and placed a stasis field around it, and then used him as a garden gnome. The Doctor found out that the Hornets remained dormant in Francesca's dead body, which was stolen by Farrow and Sally. Eventually, her mummified feet and ballet shoes would make their way to the museum in Cromer. (AUDIO: The Circus of Doom)

The Doctor finally found the earliest infestation of the Hornets in the year 1039, in a nunnery in Northumbria, which was under siege by wild dogs, possessed by the Hornets, who met the Doctor for the first time from their perspective. While there, the Doctor discovered that the Hornets had recently come to Earth, and were now looking for their lost Hornet Queen who had hidden in the body of a pig trapped in the nunnery. They eventually achieved this and attempted to escape in the leading dog of the pack, but the Doctor tried to trap the Hornets in his TARDIS. While the Doctor was trying to retrieve the Hornets in the TARDIS, he eventually managed to confront them. He realised that they were unable to take possession of the nuns in Northumbria, because they couldn't inhabit the bodies of those who had consumed alcohol.

The Hornets had managed to take possession of the Doctor, and piloted the TARDIS back to Earth, where they could escape. They escaped and encountered the younger Antonio in 1768. The Doctor searched for the Hornets in Venice for days, but he later realised that he was responsible for the Hornets' contact with Antonio, who would eventually set up his Circus of Delights. The Doctor then took the wild dog back to Nest Cottage, where it became his dog, Captain. (AUDIO: A Sting in the Tale)

The Doctor put an advertisement in a magazine to invite Mike Yates into his investigation of the Hornets. After the stuffed animals in the Nest Cottage came alive and both Mike and the Doctor were forced to retreat into the cellar, the Doctor decided to keep him up to speed, by telling him about all his encounters with the Hornets. (AUDIO: The Stuff of Nightmares) However, the Doctor later claimed that he couldn't remember putting the advertisement in the magazine. (AUDIO: A Sting in the Tale)

The Doctor wanted to finally defeat the Hornets by neutralising their queen. Therefore, with the help of Mike Yates and Mrs Wibbsey, he used Francesca's ballet shoes and his TARDIS' dimensional stabiliser to shrink themselves, so they were able to enter the hive of the Hornets, which happened to be a stuffed zebra housing the Hornet Queen herself. During the expedition into the hive of the Hornets, Mike had become paranoid and suspicious of Mrs Wibbsey, leading to his handcuffing her and directing her to the centre of the hive, resulting in a confrontation with the Hornet Queen. It was during this confrontation that the Hornet Queen revealed she had taken possession of Mike.

It was this revelation that the Doctor realised that it must have been the control of the Hornets that forced him to put that advertisement in the magazine, using what knowledge she had taken from the Doctor's mind so she could draw Mike to Nest Cottage, believing him perfect to take control since he had so many negative experiences. Since the Hornets were no longer restrained by the force shield, they took their opportunity to return to the Hornet hive, so the Doctor threatened all the Hornets by burning the whole hive. However, the Doctor realised that he could use the Hornet Queen's desire for the Hornet's royal jelly that they produced against her. He achieved this by filling Francesca's ballet shoe with royal jelly, and the Queen, overcome with the desire for the jelly, drank it out of the shoe.

The Doctor used the residual energy of the Hornets in the shoe and the sonic screwdriver's connection to the dimensional stabiliser to shrink the Hornet Queen so small she could only exist in the micro-universe. This weakened the Hornets and gave the Doctor the opportunity to escape, so he could increase their size again. This allowed the Doctor to reactivate the dimensional stabiliser, so he could put a force shield around the hive to contain all the Hornets in the stuffed zebra, sending them to the other side of the universe. This gave the occupants of Nest Cottage the chance to celebrate Christmas the following day. (AUDIO: Hive of Horror) The Doctor left Nest Cottage shortly afterwards to resume his travels in the TARDIS, leaving Captain with Mike. (AUDIO: The Relics of Time)

A return to wandering
Whilst working on K9 MKII, the Doctor arrived on Earth in 2007 and reunited with former-companion, Oliver Day, who was suffering from amnesia, which caused him to temporarily lose his memory of his travels with the Doctor. After killing a monster, the Doctor took Oliver aboard the TARDIS as his latest companion. (PROSE: Attachments)

Arriving in an alien marketplace, the Doctor and Oliver met Gravkrom-Vey, owner of the last Monkrah fish in the universe. The Doctor discovered the Monkrah had been wiped out in a civil war with the Manicoll, who also began dying soon after the war had ended, so the Doctor and Oliver helped Gravkrom-Vey release the last Monkrah. (PROSE: Plight of the Monkrah)

Soon after, the Doctor and Oliver went on the trail of the Puppeteer, an evil creature who had followed mankind's progression across the stars, and fed on the countless wars and conflicts of Earth. They followed him to Gondovan, where they met investigative archivist Annajin Valentin. Oliver fell under the Puppeteers control and tried to kill Anna. But the Doctor managed to free his mind, whilst Annajin killed the Puppeteer. Oliver, shaken by his experience on Gondovan, elected to stay behind with Annajin, leaving the Doctor to travel alone with once again. (PROSE: Puppeteer)

The Doctor teamed up with all of his other incarnations to save Gallifrey from destruction at the end of the Last Great Time War, but, (TV: The Day of the Doctor) shortly after meeting for tea with some of his other incarnations in the Under Gallery, (PROSE: The Day of the Doctor) lost all memory of the event due to the timelines not being synchronised. (TV: The Day of the Doctor)

The Doctor met archeologist and adventurer Tiger Maratha, and the two briefly travelled together, during which the Doctor made the acquaintance of Tiger's daughter, Priyanka, once offering her a bag of jelly babies. Amongst their adventures included fighting the Deathlings at Angkor Wat. However, Maratha decided to leave the TARDIS and stay on Earth to raise his family. (COMIC: The Swords of Kali)

Returning to Nest Cottage
The Doctor returned to Nest Cottage to celebrate Christmas with Mrs. Wibbsey, Mike Yates and Captain. While he stayed in Nest Cottage, someone stole the Doctor's spatial geometer, leaving behind a bag with five objects as clues. The first one, the tile from a Roman mosaic, led the Doctor and Mrs. Wibbsey to Celtic Britain. They were taken by Celtic soldiers who believed them to be Druids, and wanted to use them to assassinate the wizard in a neighbouring village, who was threatening them.

They travelled to this village, and on the way found dead husks, drained of their life essence. In the village, the Roman Emperor Claudius was posing as the wizard, who desired to escape from Rome and the troubles of being emperor. During an attack by the Celts from the village, the Doctor managed to stop them from fighting by using a voicemail message of Mike Yates from the Nest Cottage telephone he had with him. After the battle ended, Claudius attempted to usher the Doctor inside the back reaches of his tent, but failed, and the Doctor escaped before the tent vanished, but not before removing the remains of his spatial geometer that Claudius had taken. (AUDIO: The Relics of Time)

Next, the Doctor found an altered version of a poster painted by Henri de Toulouse-Lautrec. This led the Doctor and Mrs. Wibbsey to Paris in the 1890s where Lautrec's concierge had tried to frame Lautrec as a murderer of street girls, by making him doubt his own sanity. To do this, she slashed his paintings and killed Henri's muses and models, and stored their remains in his house, unbeknownst to him. With the help of Henri's muse, La Charlotte, they discovered the bodies and uncovered the truth of Henri's innocents. From this revelation, they found out that the murders were due to the action of Lautrec's concierge, in part to cover up his need to feed on those girls life force.

In an attempt to lure the Doctor, the concierge kidnapped Lautrec and took him to a cemetery, where her dematerialisation chamber was. The concierge almost captured the Doctor in his time craft, but the Doctor forced his way out. However, La Charlotte was killed before they all could escape. The Doctor then retrieved another part of his spatial geometer that was left behind. (AUDIO: The Demon of Paris)

The third object, a storybook with images of the Doctor and Mike Yates in it, drew them to a cave in eastern Europe, where the Doctor met a story teller, Albert Tiermann on his way to tell his stories to the king. But the materialisation of his TARDIS caused a blockage in the road on his route to the king. They were all forced to remain in a nearby hotel owned by Frau Herz until the morning. Albert had discovered the Doctor's copy of his storybook, containing stories he hadn't written yet. Since he was suffering from mental block, and had to tell a new story to the king on pain of death, he had a desire to obtain the book.

That night, an Ice Queen whom Albert had previously met in his childhood visited him, and further persuaded him to take the storybook. The following morning, Albert's coachman had been killed, and in an attempt to take Frau Herz hostage, the Ice Queen killed Hans, Albert's footman. The Doctor pursued the Ice Queen to a cave nearby, full of dead husks drained of their life force, where Albert revealed that all his stories were created for him by the Ice Queen, in her elaborate plan to lure the Doctor here.

The Ice Queen returned to the hotel, and threatened to kill Mike. It was then revealed that the hotel was really the dematerialisation chamber, and was in disguise for forty years, unbeknownst to Frau, all for this moment. Direct threats from the Ice Queen to Mike did not hold the Doctor, so he tricked the Ice Queen into believing he was going to accompany her, allowing Mike, Albert and Frau to escape. Then, at the last minute, the Doctor escaped, leaving the Ice Queen empty-handed. But Mike had discovered more of the spatial geometer in the draws of the hotel. The Doctor deposited Albert and Frau near the king's palace, and allowed Albert to keep the storybook, and used it to write his stories in the future. (AUDIO: A Shard of Ice)

The Doctor ran into a trap in New York City in 1976. A meteorite landed in Central Park and bestowed super-powers to local resident Alice Trefusis. The Doctor investigated the comic book cover showing the event. When the Doctor, Mike and Mrs. Wibbsey arrived, Alice was with her boyfriend Buddy. As soon as the Doctor arrived, he felt weak and drained of energy. Mrs. Wibbsey and Buddy had taken a now unconscious Alice to the ageing film star Mimsy Loyne's apartment. Alice began to use her superpowers to combat crime and stop accidents, using the alias "Starfall".

While this was going on, Mike and the Doctor came upon a dead body drained of energy, similar to the dead bodies from the previous time zones. It was at the scene where police arrested the Doctor and Mike, believing them to be involved in the death. However, while in prison, Alice rescued the Doctor and Mike, taking them to Mimsy's apartment. Buddy and Mrs. Wibbsey then found a cult working in the apartment block, chanting around the final piece of the spatial geometer. This was used to create a telepath debilitator to confuse the Doctor, causing his weakness. Mimsy captured the Doctor, but was foiled when Alice broke up the chanting cultists necessary for the debilitator. During the confrontation with Mimsy, the Doctor took the remaining spatial geometer component. In frustration, Mimsy kidnapped Mrs. Wibbsey, outright. The Doctor informed Alice that her powers would fade, but Buddy still had inspiration for his new comic book story. (AUDIO: Starfall)

Following the last item, a golden heart pendant, the Doctor and Mike went straight to Sepulchre, which took the form of a stately home, where they found Mrs. Wibbsey, who had been there for three weeks and seemed to be possessed by some intelligence. The Doctor brought the telephone from Nest Cottage, and listened to a voicemail left by Ernetina Stott, regarding the burning down of the Cromer Palace of Curios museum. While they were exploring, the Doctor, Mike and Mrs. Wibbsey found that their host, the Demon, no longer needing any disguises, sprang the trap on the Doctor, and transported them all to a dark cavern, using a mysterious green flame. He revealed he was actually working for the Hornets that had regenerated inside of Mrs. Wibbsey, who had been present within her since their last encounter with them. The Demon locked the Doctor in a sarcophagus, and started the process to extract all of knowledge of space and time from the Doctor's mind, using it to create the Atlas of All Time for the Hornets, which they could use it to locate their Hornet Queen.

A quick turnabout by Mike Yates set Mrs. Wibbsey in the sarcophagus instead, and the Atlas was reshaped only to contain Mrs. Wibbsey's knowledge of time. The Doctor convinced the Demon to cooperate with him, and they reconfigured the sarcophagus' functions to transport anyone in it to anywhere in the Atlas. Therefore, using what little remained of the Atlas, the Doctor transported the sarcophagus and the Hornets to the Cromer Palace of Curios, where it caused the museum to burn down with a green flame, quickly destroying the Hornets. However, the Doctor was able to rescue Mrs. Wibbsey, but with the loss of the Hornet, it caused the destruction of the Atlas and Sepulchre. The Doctor, Mike, and Mrs. Wibbsey escaped in one direction, using the TARDIS to go to Nest Cottage, and the Demon escaped in another direction, free to roam the universe. While the Doctor, Mike and Mrs. Wibbsey tried to celebrate a second Christmas at Nest Cottage, someone knocked on the door, and Mrs. Wibbsey screamed as the unknown visitor tried to break in. (AUDIO: Sepulchre)

As they broke down the front door, it was revealed that they were Robotov robots, who were instructed to take the Doctor. When attempting to resist them, Mike was knocked unconscious, and the Doctor and Mrs. Wibbsey were captured by the robots and were transported to the far future by a wormhole. The Doctor was brought before the Tsarina, the wife of the Tsar, the figurehead of the Robotov Empire, an empire entirely ruled by sentient robots, and requested the Doctor help her three-year-old son, Alex, the cyborg heir to the Robotov throne. The Tsarina believed that the Doctor was "Father Gregory," a former ally of the empire, but betrayed them to their enemies.

After improving Alex's condition, the Doctor and Mrs. Wibbsey were invited to a banquet with the Tsar and the Tsarina. However, it was interrupted by a raid instigated by enemies of the Robotovs, and they abducted Mrs. Wibbsey. When she was taken to their base, she met the real Father Gregory, who looked exactly the same as the Doctor, and he revealed that he was the one who brought them to the future. However, the Doctor arrived to rescue Mrs. Wibbsey, where he discovered that Gregory had allied himself with the Skishtari and during the raid, implanted a Skishtari egg in Alex's chest to be released at the heart of the Robotov Empire. However, realising the error of his ways, Gregory removed the egg from his chest, and saved Alex's life by transplanting his own heart for Alex's, which killed Gregory. Attempting to save Alex, he and his guardian, Boolin, escaped in a shuttle with the egg, and travelled through the wormhole. Attempting to pursue them, the Doctor and Mrs. Wibbsey arrived back in Hexford, but in the year 1861. (AUDIO: Tsar Wars)

As they explored Hexford, the Doctor and Mrs. Wibbsey discovered that they arrived ten years after the shuttle arrived in Hexford, and the shuttle crash caused an accident which resulted in Boolin losing his memory, and Alex becoming facially disfigured. After the accident, Reverend Dobbs took care of them, making Boolin his servant, and Alex his ward. Eventually, Alex discovered the Skishtari egg, and used it punish people who upset him.

When the Doctor found Alex and Boolin, Boolin began to remember his lost memories, and when he attempted to persuade Alex to acknowledge his identity as an heir to an intergalactic empire, Alex refused to believe it, and used the egg to consume Boolin. When Alex ran away from them, the Doctor tried to pursue him and convince him to give up the egg. However, when Reverend Dobbs arrived, Alex went into a rage and lost control of the egg, which consumed them all. (AUDIO: The Broken Crown)

When the Doctor and Mrs Wibbsey awoke, they were in a vast cavern, where they came across a young man who sounded like Alex called Aladdin, who said he was sent into the cavern to uncover a magic lamp for a mysterious magician. As they all looked for the lamp, the chamber filled with gas and they fell asleep. When they awoke, the Doctor's scarf had vanished and they met the Magician, who looked like Boolin. After further explorations, the Doctor became separated from the group. While exploring on his own, he found his scarf had become animated and it began to talk to him. He followed the scarf and rejoined with Mrs. Wibbsey, Aladdin and the Magician, and they found the lamp. When Aladdin rubbed it, the Scarf emerged and allowed Aladdin three wishes. They scarf revealed that the situation they were in was a projection made by Alex's mind to represent the quest for the Skishtari egg, and the characters were the victims consumed by the egg in Hexford. With the Doctor's assistance, Aladdin remembered his former life as Alex, and wished to stop the projection, and be released from the egg back to Hexford.

After arriving back in Hexford, the lamp turned into the egg, and Alex wished, at the Doctor's request, that they travel to Christmas Day, 2010, the day they were taken by the Robotov robots. Reunited with his TARDIS, the Doctor took Boolin and Alex into the future, back to the Robotov Empire, while Mrs. Wibbsey remained at Nest Cottage. (AUDIO: Aladdin Time)

Exploits with Ann Kelso
Tracing an anomalous energy signature on Earth, the Doctor fought the Sinestrans with Ann Kelso, who he took in the TARDIS per her request. (AUDIO: The Sinestran Kill) He took her into the future to show her the advancement of society, landing in DrashigWorld on the day of its closure due to a visitor fatality. (AUDIO: Planet of the Drashigs)

The Doctor later took Ann to 1850 Nottinghamshire where they met Lord Byron. (AUDIO: The Enchantress of Numbers) Their hunt for the Sinestrans led them to discover that something was wrong with time. (AUDIO: The False Guardian)

The Doctor eventually determined that he was dealing with the heirs to the conspiracy masterminded by Mavic Chen, who had decided to mount their own campaign of conquest. The Doctor was able to defeat most members of the organisation, but then realised that "Ann" was actually a fake identity of SSS Agent Anya Kingdom, who had been programmed with an alias to ensure that the Doctor would target the right members of the conspiracy. The Doctor was able to expose the deception, but decided to leave Anya, despite her request to travel with him. (AUDIO: The Perfect Prisoners)

Lone travels with K9
The Doctor landed on a Vorgan Space Platform, and the TARDIS was captured by the Vorgs. The Doctor escaped into the depths of the complex, and managed to steal a field generator from a sleeping guard. He used this to deflect the Vorg's laser blasts. While making his way back to the TARDIS, the Doctor was spotted by a squad of Vorgs, who summoned a Mobile Neutron Cannon to shatter the Doctor's force shield. At that very moment, a fleet of battle cruisers arrived out of a white hole and began attacking the platform, as they sought to reclaim ships captured by the Vorgs. The ensuing chaos created enough of a diversion for the Doctor to escape in the TARDIS. (PROSE: The Doctor's Journal)

Looking for K9
While travelling solely with K9, the TARDIS was caught in a Gravitational Tractor Beam, which shook up the vessel and its passengers. After a moment, K9 disappeared entirely from the ship. Unable to discover where K9 had been sent to, the Doctor went on many travels alone. (COMIC: K-9's Finest Hour)

Arriving in Bethlehem four years after Jesus's birth, the Doctor encountered a time traveller known as the "Fourth Wise Man" and became trapped in a void inhabited by a god-like entity that wanted his brain. The Doctor completed a complex crossword puzzle, which led him to freedom. (PROSE: The Doctor's Cross Word)

The Doctor visited Zaggar-Six, where he came into the possession of multiple Zaggan pound notes. He eventually found his way to the outskirts of a small town in the English countryside on Earth, where he went into a shop to restock up on foods. Inside, he found the "Old" Grubb completely petrified with fear of something coming. At this point, the shop was attacked by a Roman-style robot, which killed the shopkeeper without mercy and attempted to kill the Doctor. The robot malfunctioned after being confused by the Doctor's biology, but the Doctor was soon attacked by reinforcements of robots in the Iron Legion, who shot at him as he entered the TARDIS.

The Doctor learned that he had slipped into a dimension duct to an alternate world where Rome had never fallen and where a vast empire ruled the galaxy. Landing in the middle of a royal ceremony, he met with General Ironicus, who threw him into the Ectoslime after he refused to give him the secrets of the TARDIS. The Doctor was able to avoid it killing him by telling it a joke in its native language, thus befriending it, but the Doctor was enslaved for this and taken on board the Imperial Air Galley. He escaped with the help of ex-gladiator Morris, while also being joined by Vesuvius, a robot with a flame attachment to his head, although Morris suffered a fatal injury and died. In the catacombs, the Doctor activated the genetically engineered Bestiarus and programmed them to start a revolution against Rome.

The Doctor eventually met with what was purportedly Adolphus Caesar's mother Juno, who the Doctor revealed was really Magog, a Malevilus whom had secretly influenced Rome into conquering the galaxy, and reverted to his original form. Magog had the powers of physical manipulation, and tortured the Doctor for his actions—turning his body inside out and twisting the time around his body, as well as other things. The Doctor was able to point a camera at the beast, revealing to the people his true nature and causing them to join in with the uprising. Magog did not care about this, as he knew that he could still force his will over them, and forced the Doctor to take him into the TARDIS, where he was tricked into flicking a switch which flung him into an empty dimension, trapping him for eternity. Back on Earth, the remaining Malevilus were killed by the besieging Bestiarus, Vesuvius was crowned the new emperor and the Doctor left for a vacation in Benidorm. (COMIC: Doctor Who and the Iron Legion)

Partway to Benidorm, however, the Doctor had to force a landing on the planet Zom to repair his time-space stabiliser. In the city of Zombos, he discovered a society where emotions were the only crime, and any signs of emotion were removed by the Harmoniser. The city's police, the Moderators, discovered the Doctor's interference and took him to the Moderator General., where he was attached to the Ultra-Harmoniser—a piece of technology that wiped the mind entirely. Before his mind could be wiped, however, he was saved by the Zom Emotional People's Organisation, who arrived to save the machine's previous victim, Freddy Feel-Good. ZEPO was a resistance group of fighters who had gained emotions, although each member only held one main emotion, which became their name. Deciding that the Doctor had to be one of them if the Brains Trust wanted him wiped, the group decided to take the Doctor with them, helping him fly out of the city on one of their ZEPO fliers. Outside the city in the rebel camp, they introduced each other to him. Their silly personalities and names caused the Doctor to laugh, which the group's bible had predicted their saviour, the Great Emoter, to be able to do. The group soon realised that the Doctor held many emotions and could switch between them easily, making them believe even further that he was the Great Emoter.

At the rebel camp, the Hates, a ZEPO splinter group, had collected a group of blood-eating bugs named Barabara, who they released to eat the Moderators that had found the camp. When the Doctor was bitten by the bugs, they quickly died off, while they quickly ate the Moderators without worry. The Doctor realised that adrenaline, the chemical released by creatures under emotional stress, was poisonous to the bugs—meaning that while ZEPO was safe, those in the city were not. As a large shipment of Barabara the Hates had placed inside the food conveyer began attacking the city, the team sped to warn the Brains Trust of the threat. The Doctor stole the teleportation gear from one of the consumed Moderators and teleported to the Brain Trust.

The Doctor explained the situation to the Brains Trust, who agreed that losing what they had built was more favourable to losing their people. Before they could undo the process however, they were attacked by the Moderator General, who refused to remove emotions to his "perfect society". He killed all of the Trust before being knocked out by the Doctor. Imitating the Moderator General, the Doctor broadcast a message ordering those in the city to reconnect to their harmony booths, which he was able to use to reverse the process. As the people's blood was now poisonous to the Barabara, they instead began attacking the Moderators. The city was left without their totalitarian rulers, leaving ZEPO in charge. The Doctor decided to leave—much to the dismay of ZEPO, who still saw him as his saviour. After a few days of repairs on the TARDIS, he was able to leave, accidentally leaving behind readings of his brain's E-wave patterns. ZEPO decided to use these to repair the citizens' emotions, leaving everyone in the city with the personality, quirks, and emotions of the Doctor. Leaving them behind, the Doctor exclaimed that they would grow out of the phase. (COMIC: City of the Damned)

The Doctor finally tracked K9 down, where he learned that K9 had been grabbed accidentally by a teleportation beam that was meant for him. The tube which K9 had beamed into had no oxygen, meaning the Doctor was meant to suffocate in front of his capturers. At this point, K9 had already defeated his kidnappers, much to the Doctor's admiration. (COMIC: K-9's Finest Hour)

Unfinished business at Nest Cottage
After a few months of travelling, the Doctor arrived back in Hexford several months after he left Mrs. Wibbsey. When he returned, he found that Mike Yates, UNIT and his second incarnation had taken up residence there to investigate strange goings-on in the skies above Hexford. Upon arrival, a Skishtari spacecraft had appeared above Hexford, intent on retrieving the egg, which the Doctor had buried under Hexford in 1861. The Doctor also discovered that the Second Doctor had been assisting the Skishtari by planting alien trees which made Hexford invisible to the rest of the world. The Skishtari spacecraft began to remove Hexford from the ground, and drag it through a wormhole to the future. The Doctor attempted to use the TARDIS to prevent this, but failed, leaving the Doctor and Mrs. Wibbsey in the TARDIS, while everyone in Hexford had been taken to the future by the Skishtari. (AUDIO: The Hexford Invasion)

After spending several months locating Hexford through time and space, the Doctor and Mrs Wibbsey found it. Just as they arrived, the Robotov soldiers attempted to infiltrate Hexford, knowing it contained a Skishtari egg. However, the Second Doctor kidnapped Mrs. Wibbsey, and took the Skishtari egg as it began to hatch. He took the egg to the Skishtari mothership, where he revealed that the Second Doctor was a clone created from the DNA that the Skishtari took from the Doctor after their last encounter, specifically designed to retrieve the egg. Suddenly, Alex appeared and revealed he was now the Tsar of the Robotov Empire. He attempted to pacify the creature in the Skishtari egg, since he was mentally linked with it when he lived in Hexford for ten years, and ordered the creature to kill the other Skishtari. After that, Alex took the Skishtari away with the Robotov invasion force, and both Doctors united to pilot the Skishtari ship, followed by Hexford, through the wormhole back to England, 2011. After depositing Mrs. Wibbsey back in Nest Cottage, the Doctor left in the TARDIS. (AUDIO: Survivors in Space)

Quest for the Key to Time
After completing repairs on K9, the Doctor was called upon by the White Guardian to find the Key to Time's pieces and assemble it to bring the universe into balance. For his quest, the Doctor was given a new companion by the guardian, a Time Lady named Romanadvoratrelundar, whom the Doctor decided to call Romana. Despite not being too fond of each other, they managed to find the first segment to the Key on Ribos, which was disguised as a piece of Jethrik two con artists were using in their schemes. (TV: The Ribos Operation)

The Doctor and Romana tried finding a segment on the crime-ridden Earth colony Vyga 3. However, it turned out to be a weapon which emitted a fluctuating chronon wave when activated, killing a group of criminals who were trying to obtain it. (COMIC: The Seventh Segment)

While searching for the second segment, the TARDIS was diverted to Ashkellia after a breach in the higher dimensions released a chronometric pulse that disrupted the tracer's ability to find the next segment. Although the Doctor was tricked into reactivating Paul Neville's psychically-controlled castle, unaware that he had the necessary means of controlling it in the form of powerful psychic Huvan, he was subsequently able to prevent Huvan becoming the new host to the power of the Old One known as Valdemar, sealing the breach and allowing him and Romana to continue their quest. (PROSE: Tomb of Valdemar)

They set out to find the second segment on Calufrax, but instead landed on Zanak, where they became caught in the middle of a revolution between pirates, led by the Captain, and the psychically gifted Mentiads, who grew in number each time their planet materialised over another for riches and resources. Defeating the Captain and his nurse, the Doctor revealed to Romana that Calufrax, which was being held as a miniaturised trophy, was the second segment. (TV: The Pirate Planet)

The Doctor and Romana next journeyed to Boscombe Moor, where they found the third segment as a necklace belonging to the intergalactic criminal Cessair of Diplos, who had been posing as an ordinary Earth woman for centuries after she had stolen the segment while it was the Great Seal of Diplos, and used its transformative powers to take on different forms. Entering a ship stuck in hyperspace above a stone circle, the Doctor found her jailers and, as they did not know what she looked like, tricked them into identifying her, and they imprisoned her in the form of a stone. The Doctor then sent them through hyperspace to their intended destination. (TV: The Stones of Blood)

While the Doctor and Romana searched for the Key, they were interrupted by a network of spatial teleportation paths created by a malfunctioning time cabinet intersecting with Earth's ley lines, which were being used by Hsien-Ko. They were forced to disrupt the teleport system while also deflecting Hsien-Ko's attempt to draw Magnus Greel's cabinet into the present day. (PROSE: The Shadow of Weng-Chiang) Afterwards, the Doctor and Romana took a break from searching for the Key. (PROSE: Heart of TARDIS)

Later, the Time Lords contacted the Doctor, telling him that they needed him to go on a mission. The Doctor, however, left them after learning that the Brigadier had been captured by a terrorist group. The Doctor discovered that the group had drawn him in to avert a disruption to a pocket universe created by an old experiment. Romana was contacted by the Time Lords, who revealed that this was the disruption they had wanted the Doctor to investigate, as it was actually caused by a TARDIS crashing into the pocket universe, with the Doctor being diverted because it was the TARDIS of his second incarnation. After releasing the Second Doctor from the pocket dimension, the Fourth Doctor and Romana continued their quest. (PROSE: Heart of TARDIS)

Searching for another segment of the Key, the Doctor was imprisoned in a dungeon for theft, but Romana managed to negotiate his release. (PROSE: Pericles)

Looking for the fourth piece, the Doctor and Romana travelled to Norfolk in 2011, where they found the fourth segment as a meteorite which was giving former astronaut Millicent Ferril the power over metal. To stop her from allowing the Conquist to invade Earth, the Doctor was forced to disperse the piece of the key causing it to reform in another time and place. (AUDIO: Ferril's Folly)

While looking for the fourth segment on Tara, the Doctor decided to take a relaxing fishing break while Romana went to look for it. Though successful in finding the piece to the Key, they both were forced into the political power struggle on Tara, as Romana was identical to a princess being held captive by Count Grendel, who wished to use her to claim the throne before his cousin. The Doctor exposed Grendel's plans and went on his way with Romana to continue the search. (TV: The Androids of Tara)

Taking a minor detour to England, the Doctor realised that a series of offensive e-mails being sent to an estate agent's office were the work of the Glarn, who often tried to undermine the morale of the planets they sought to conquer before actually attacking. The Glarn were convinced to retreat after the Doctor persuaded the office workers to send jokes back to the Glarn, forcing them to withdraw. (PROSE: The Glarn Strategy)

The search for the fifth segment brought the Doctor and Romana to Delta III where the Swampies worshipped an overgrown squid called Kroll, who was attacking a human mining base. Putting himself in harm's way, the Doctor found Kroll had swallowed the segment of the Key and was transformed by its properties. Allowing himself to be grabbed by the giant creature, the Doctor was able to use the tracer to reclaim the segment, transforming Kroll back into smaller squids in the process. Reclaiming the piece, the Doctor and Romana returned to search for the last segment. (TV: The Power of Kroll)

The Doctor and Romana investigated a mysterious painting in Kensington which turned out to be a painting that showed the viewer their death, and had been stolen from the Braxiatel Collection. He decided to take it away from the Art Gallery in which it hung, and destroy it, but the painting was stolen by UNIT Operative Ruth Matheson and placed in the Vault. (AUDIO: Tales from the Vault)

While searching for the sixth segment, the tracer brought the Doctor and Romana to Rome during the time of the Roman Empire. Exploring their surroundings, the Doctor decided to watch the play Luna Romana as a way to confuse the Black Guardian. He had to save Romana from falling off the temple roof and then told her that he knew that the segment that was in Rome was actually the fifth segment. He admitted that he was deliberately avoiding the Sixth Segment as he thought that no-one should have that power, not even the Guardians. (AUDIO: Luna Romana)

Searching for the final segment brought the Doctor and Romana to Atrios, a war-torn planet being attacked by the nearby computer-planet Zeros. There, they met the Shadow, an agent of the Black Guardian. Unfortunately, the final segment was in the form of Princess Astra of Atrios. The Doctor completed the Key, and then quickly separated it back into its original components to prevent the Black Guardian from getting it. Fearful the Black Guardian would return for revenge, the Doctor installed a randomiser in the TARDIS controls, (TV: The Armageddon Factor) having built it from bits and pieces he found in the TARDIS. (PROSE: The Fall of Yquatine)

Hiding from the Black Guardian
On the run from the Black Guardian, the Doctor sent K9 to pilot the TARDIS to one-thousand planets across time and space to lead the Black Guardian on a wild goose chase. Waiting for the TARDIS' return, the Doctor and Romana took up residency in London in 1929, becoming the Lord and Lady of the Manor. After he finished his machine, the Doctor detected alien activity and took Mabel Dobbs along with him as Romana wasn't available. He travelled to Hampshire and found a spaceship in the grounds of a country house, and was attacked after trespassing on the ship. Not knowing that Romana was at the house, he saved her from a Valjax called Lady Florence Bassett, who wanted to take her body. Florence attacked the Doctor for meddling and planned to kill him. After Florence died, he made his way back to London before Romana knew he was missing. (AUDIO: The Auntie Matter)

The Doctor and Romana visited Prague, which allowed the Doctor to deal with unfinished business left over by his first incarnation. (PROSE: Life from Lifelessness)

The Doctor, Romana, and K9 encountered a frog-like being named Bolog, who had a fleet of ships at his command hidden on the far side of the moon. The Doctor was able to stop him by sending his ships into orbit around the sun with a banana. (COMIC: Death to the Doctor!)

The Doctor and Romana found themselves embroiled in stopping the Quell from destroying the Warren family through several generations from the late 12th century all the way to the 21st century. (AUDIO: The Warren Legacy)

The new Romana
While repairing K9, the Doctor found Romana had regenerated into Astra's form, much to his displeasure. The randomiser landed the TARDIS on Skaro, where the Daleks were excavating the remains of the Kaled base to restore Davros. The Doctor also faced the Movellans, an android race at war with the Daleks. Having reached an impasse of logic, they both needed someone to reprogram their respective computers for "illogical" movements that would give either side an advantage. Winning the Movellans over, the Doctor allowed them to take Davros in cryogenic custody to await trial for his crime of creating the Daleks. (TV: Destiny of the Daleks)

The Doctor partially bypassed the randomiser to take Romana on a relaxing holiday to Paris, where the Doctor discovered a Jagaroth named Scaroth was splintered into twelve selves throughout time after his spaceship exploded; the explosion's radiation affected the primordial ooze, thus beginning life on Earth. The Doctor, Romana and detective Duggan succeeded in stopping Scaroth from preventing his spaceship from exploding. (TV: City of Death)

After forgetting K9's birthday, the Doctor took him and Romana to a planet made entirely of candy, where he accidentally caused cakes to become sentient. (PROSE: Special Occasions: 1. The Not-So-Sinister Sponge) He next became Santa Claus in 1970s London and broke into the Brigadier's house to leave presents for his old friend. (PROSE: Special Occasions: 3. Better Watch Out, Better Take Care)

The Doctor attended the Queen's re-coronation, (PROSE: The Dying Days) and visited a conference on Mars. (PROSE: Beige Planet Mars) Due to the faulty randomiser, the Doctor and Romana found themselves in Paris 2000, and they defeated a Minotaur who had kidnapped humans throughout history. (COMIC: The Forgotten)

The Doctor became trapped in the Void along with seven other incarnations, but was able to work with K9 to send a distress call to the Ninth Doctor. He and the others were able to form a dimensional bridge to allow the Eighth Doctor to escape, and were then joined by the War Doctor, followed shortly by the ninth, tenth and twelfth incarnations, who ventured into the Type 1 TARDIS responsible for the disturbance. Forming a plan with the trapped Eleventh Doctor, the Doctors joined their TARDISes to pacify the Type 1 into a peaceful state and return the universe to normal. (COMIC: The Lost Dimension)

The Doctor later received a distress signal and arrived on Chloris, a lush and verdant world with only small quantities of metals, all of which were controlled by its ruler, Lady Adrasta. The Doctor was sent for execution, but managed to avoid it, deciding to investigate the creature he was supposed to be fed to. He found it to be an imprisoned Tythonian that had been sent by its people to set up a trade agreement with Chloris. Deciding to end Adastra's tyranny, the Doctor allowed the Tythonian to kill her and let a new reign of peace be set up between the two species of the planet. (TV: The Creature from the Pit)

When the TARDIS materialised on the Rock of Judgement, an asteroid prison used by the natives of the Uva Beta Uva system, the Doctor, Romana and K9 became involved in a complex scheme that would allow the telepathic mutant Xais to resurrect herself after her execution, her mind imprinted on a uniquely fashioned "death mask" that would allow her to possess those who wore it once the helicon that made it had been imprinted with her mental pattern. Learning that High Archon Pyerpoint had been attempting to use Xais to set himself up as ruler of the system, the Doctor eventually trapped them both on Planet Five, Pyerpoint dying as he tried to make Xais share the secret of immortality with him and Xais left trapped as her mask was lost and the helicon on the planet left raw and unrefined. (PROSE: The Romance of Crime)

Deciding to return some library books before they became overdue, the Doctor learned of a temporal rift leading to Earth in 1930, which resulted in him learning about the ruthless Zodaal, a criminal from a distant planet who had imprinted his mind into a cloud of radmium, now intended to destroy Earth to channel the power of its destruction so that he could imprint himself permanently onto a new host. The Doctor was able to force his ship to take off after sabotaging Zodaal's equipment, his chosen host committing suicide before he could take control and leaving Zodaal to drift helplessly through space. (PROSE: The English Way of Death)

Trapped in Grey Space with Romana, the Doctor was challenged to a game by two entities. After failing their games, he was erased from existence. However, he was later restored by the First Doctor. (AUDIO: Seven to One)

The TARDIS then arrived on the space liner Empress, which had become locked together with a private ship, the Hecate, after colliding with it upon emerging from hyperspace. The Doctor and Romana met Tryst, who had a Continuous Event Transmuter machine. However, some Mandrels from Eden had somehow gotten on board. The Doctor later discovered he had been lied to, and Mandrels actually decomposed into the addictive drug vraxoin. The Doctor thwarted the drug-smuggling plan of Tryst and the pilot of the Hecate, separated the two ships, and returned the Mandrels to Eden. (TV: Nightmare of Eden)

Annoyed at the lack of donuts in the TARDIS food machine, the Doctor set course for the Vita Novus Health Spa and defeated Karna, the director of a company dedicated to creating "the Beautiful People", which consisted of slim and beautiful human beings. (AUDIO: The Beautiful People)

The Doctor and Romana landed on the Myriad, which was looking for evidence of the Doctor, as he had previously helped their colony. After exploring the ship, the Doctor discovered that there was a Pyralis prison on the planet the ship was orbiting. After defeating them, he programmed the ship to a habitable planet and told Suri to stop the search for him. (AUDIO: The Pyralis Effect)

After saving eleven planets and two space stations, the Doctor took up autograph collecting. Visiting Notting Hill Gate studio's to meet celebrities, the Doctor met Prince Tarvill, an exile from the planet Frentos. He saved Tarvil from four armies who had come from various points in Fretos's past. After sending the armies back to their original time, the Doctor returned Tarvil to Frentos, at a point in time where no one on the planet had heard of him. (PROSE: The Clanging Chimes of Doom)

Whilst in the middle of conducting TARDIS repair, the Doctor and Romana were caught in the middle of a sacrificial ceremony for a "god" called the Nimon. They discovered that this "god" was actually a parasite alien preparing Skonnos for the rest of its species. The Doctor succeeded in preventing the teleport from bringing more than two extra Nimon before the Nimon killed themselves as an accidental side-effect to their final gambit. With the help of the Anethans originally sent to be life-force sacrifices for the transporter, the Doctor destroyed the remaining Nimon before departing with Romana. (TV: The Horns of Nimon)

The Doctor then tracked down the Great One of Metebelis III, on a council estate on Earth and foiled her plot to avenge her species by destroying Earth. (PROSE: Return of the Spiders)

The Doctor and Romana landed in Budapest in 1980 in order to take in the sights. The Doctor was mistaken for a vampire by Celia Soames after he was caught standing over a dead body, but he proved himself by showing his reflection, and explained to Celia that the wounds on the body weren't made by a vampire. He went with Celia to the labyrinth underneath Buda Castle, where he met with a mysterious being but was arrested for trespass.

The Doctor later went to Anita Kereki's flat to find out what information Romana had discovered. In the flat, he tried to find out from Zoltán Frid why he was attacking the people of Budapest. Frid told him that he wanted information and that he planned to sire the Doctor to get information from the whole universe. He used a hypnotic suggestion which he planted in Celia's mind to kill Frid and cure all his victims. (AUDIO: The Labyrinth of Buda Castle)

Shada
The TARDIS was sent a distress signal from Cambridge in 1979, sent by a retired Time Lord known as Professor Chronotis. (PROSE: Shada) Sources diverge on when and how their trip ended; the Doctor and Romana were kidnapped (TV: The Five Doctors) and then either returned without seeing Chronotis, (WC: Shada) or they were returned and saw the Professor as planned. (PROSE: Shada; HOMEVID: Shada)

While they were on a punt up the Cam, the Doctor and Romana were taken by a time scoop to the Death Zone on Gallifrey, but were caught in a time eddy and failed to arrive in the Death Zone. (TV: The Five Doctors) They were returned to the Cam (HOMEVID: The Five Doctors) either to the time they left (HOMEVID: Shada) or several hours later (WC: Shada) when Borusa was sealed in the Tomb of Rassilon. (TV: The Five Doctors)

In the account where the Doctor returned hours later, he forgot his intent to visit Chronotis, went back to the TARDIS and planned a trip to Brighton. (WC: Shada) He landed on Maruthea, at the heart of the Time Vortex, (COMIC: Party Animals) but quickly left. (COMIC: The Incomplete Death's Head) In this account, he would not know of Shada until his eighth incarnation. (WC: Shada)

According to the accounts where the pair were returned to the moment they left, the Doctor met Chris Parsons and Clare Keightley, who helped him to fight Skagra. Skagra attempted to steal The Worshipful and Ancient Law of Gallifrey so he could break into Shada and retrieve Salyavin from his imprisonment. Without realising that Salyavin had escaped, and was living in retirement under the alias "Chronotis", the Doctor had to foil Skagra's plot, which involved taking Salyavin's power to project his mind into other minds, so he could use it to shift his mind into the minds of all life in the universe, using his Krargs. After defeating Skagra, the Doctor imprisoned him in his own ship, and decided to allow Salyavin to remain on Earth. (TV: Shada; PROSE: Shada)

After the adventure was completed, the Doctor locked Shada away in a forgotten part of space. He wiped his memory of the events of the adventure so that he would barely remember anything about it, leaving little more than a crude drawing of the planets around where he left it as a hint for its true location. According to this account, the Doctor would not remember anything about Shada until his eleventh incarnation. (COMIC: The One)

After Shada
Landing in Brighton in 1833, too early for the Brighton Pavilion, the Doctor decided to stay around for its opening. Noticing that there was a waxworks in town, both Romana and the Doctor went to visit it, where the Doctor noted to its proprietress, Mary Barnes, that its tableau of Horatio Nelson was wrong. Investigating Goole, the Doctor found out that he and Marie came from the Slough, and they had come to Earth to experience emotion. He accidentally over-clocked Goole and Marie's androids, causing them to explode. He rescued "Romana" and took her to TARDIS and discovered that Goole was impersonating her. He defeated Goole by freezing him in the TARDIS and left him with Mary Barnes. (AUDIO: Gallery of Ghouls)

Taking his basic time-travel proficiency test on Romana's insistence, the Doctor materialised on the G-Lock in 3012, where several locals immediately hailed him as having saved the G-Lock from destruction, even though he'd never been there before. Realising that he was dealing with the consequences of a future trip, the Doctor resolved to go back in time and learn what had happened on his previous visit, even though all available information suggested that he was destined to die saving the G-Lock. After making a second trip to the G-Lock, as well as a trip back to 2815 to investigate the origin of the G-Lock, the Doctor learned that the Beautiful Death was powered by the Arboretans as part of Doctor Koel Paddox's attempts to harness their ability to relive their own lives, but his actions had created a rift in reality that would allow the entity known as the Repulsion, a being of pure death, to gain access to this universe. The Doctor was able to trick the Repulsion into transferring itself into K9, allowing him to then upload the Repulsion into the suicidal control computer ERIC and destroy them both. (PROSE: Festival of Death)

The Doctor visited East Berlin, reunited with Edward Grainger and stopped an alien ambassador from instigating a war between Cuba and America. (PROSE: Checkpoint)

The Doctor and Romana went to an inter-galactic conference, where the Vandelanian ambassador was arguing against research on sub-microscopic species, as delegates on behalf of the Time Lords. He and Romana were held at gunpoint by a Voton spy, who had planted a trigger for a bomb in the Ambassador's voice patterns, intending to kill everyone at the conference and start a galactic war. The Doctor interrupted the conference, enraging the ambassador, and had the Voton arrested. (PROSE: The Voton Terror)

Lone adventures with K9
Now separated from Romana, Doctor and K9 encountered a space amoeba, who fed on time. Time began to reverse, causing the Doctor to drift back through his own past, turning him back to his third, second and first incarnations. The space amoeba took him back to when his first incarnation powered up his TARDIS. However, the two Doctors worked together, and moved time forwards, reducing the entity to a puddle on the TARDIS floor. (COMIC: Timeslip)

Falling through time without K9 or his TARDIS, the Doctor was transported to many places that tested his sanity to the limit. Escaping each trap, the Doctor discovered an entity, who resented him for his constant meddling in the affairs of the universe, was responsible for these events. The Doctor tricked the entity into condemning itself to a lifetime of insanity, which loosened the entity's control over him. (PROSE: The Fear)

On the planet Koblos, the Doctor was put on trial by the Time wardens for crossing an illegal time-zone and sentenced to two-hundred-and-fifty years in prison. Whilst in prison, the Doctor discovered the trial had been set up by a corrupt Time Warden who wanted to sell his TARDIS in the black market. With K9's assistance, the Doctor escaped and stopped him. (PROSE: The Two-Timer)

During a visit to Neto, the Doctor defeated a monster that had hidden away inside his TARDIS ever since he was in his first incarnation. (PROSE: Stowaway)

K9 and Sharon
Investigating a supposed UFO crash landing in a Blackcastle steel mill, the Doctor allied with Sharon Davies to protect Beep, the last of the Meeps, from the Wrarth Warriors. However, he soon discovered that Beep was a dangerous criminal. Enraged that he had been tricked, the Doctor allied with Wrarth Sergeant Zogroth to entrap Beep. He was unable to stop Beep's repaired starship from activating its star drive and leave Earth with Sharon, but reduced its power enough to prevent the destruction of Earth. The Wrarth Warriors arrested Beep and freed Sharon. (COMIC: Doctor Who and the Star Beast)

Attempting to return Sharon to Blackcastle, the Doctor landed inside the space freighter Spacehog in the New Earth System. During an attack on the ship by Werelox, the Doctor was scratched by the leader of the Forty-ninth Werelok Pack, Brill, but K9 stunned him. Infected by the venom in the scratch, the Doctor began turning into a Werelok. Retaining enough of his original mind, the Doctor took a sample of the venom and vanished into the TARDIS with K9. With K9 stopping him from going back before he was cured, the Doctor spent three months fighting off the infection before he created an antidote and returned to his true form, with only ten minutes having passed on board the Spacehog. On the planet New Earth, the Doctor hypnotised Brill and learnt that the Werelox were working for the Daleks.

The Doctor boarded the Dalek battlecraft with K9 and Brill and discovered a room Brill called the Room of Many Centuries. Capturing the Doctor, the Daleks told him that they planned to isolate traits from several creatures in their zoo in their cloning and use the New Earth System as a Dalek breeding ground. After escaping the Daleks, and realising the Room of Many Centuries contained time travel technology, the Doctor returned to the TARDIS and materialised in the room. K9 and Brill cleared the secure room of Daleks, and the Doctor froze the battlecraft, the Daleks and the Werelox in one moment in time and space forever when he disconnected the time-space rationaliser of the time transporter. Sharon decided she was in no hurry to return to Blackcastle, and was having fun in the System. (COMIC: Doctor Who and the Dogs of Doom)

While attempting to educate Sharon in advanced science, the Doctor found the TARDIS being ripped in half. They found themselves in a blank dimension, where a woman with psychic powers called Brimo resided, who created whatever she wanted by drawing in energy from N-Space. The Doctor cut off her source of psychic energy when the TARDIS was stuck in the gateway between N-Space and her dimension, and engaged in a battle of minds, where Brimo slowly ran out of power in the dimension. When Brimo had only enough power for one more move, the Doctor defeated her by making her think of what she feared most, trapping her in the Eternity Capsule. The two then travelled with half of the TARDIS four years into the future to meet with its other half; however, due to a malfunction, both of them aged four years in an instant, as the chrono-compensator was malfunctioning. (COMIC: Doctor Who and the Time Witch)

The Doctor took Sharon to a planet he frequented, and there they met his old friends. Sloth-like creatures were used to create dream states for people to have adventures. Unfortunately, the species had become annoyed at being used like this and began attacking their owners. At the end of the adventure, Sharon chose to stay behind with someone she fell in love with, since she couldn't go back home as a woman in her 20s. (COMIC: Dreamers of Death)

More adventures with K9
While travelling through time and space, the TARDIS was sucked into a vortex which caused it to materialise on an uncharted planet. There, the Doctor discovered a chained up man claiming to be Prometheus of ancient Earth legends. Prometheus had been held in this realm for punishment of giving the "spark of life" to humanity. Released with the help of K9, Prometheus led the team to the planet of Olympus. There, Zues argued that humanity's dark nature was much more devastating than any of their positive exports, leading Prometheus to again steal the spark of life as the team fled in the TARDIS. Zues hastily threw a bolt of lightning at the team, scrambling the ship's controls. Materialising in deep space, Prometheus left from the shuttle. (COMIC: The Life Bringer!)

Final voyages with Romana
Before repairing K9, the Doctor and Romana searched for a vampire on Earth, who had been trying to control himself. When the vampire went out of control, the Doctor was forced to stake him. (PROSE: I Was a Monster!!!)

After their holiday at Brighton, the Doctor took the TARDIS to the Leisure Hive, due to Romana's urging for a technologically advanced place of relaxation. However, during the adventure to repair a rejuvenation machine, the Doctor ended up ageing hundreds of years. A genetically created Argolin, named Pangol, decided to take over, but thanks to the Doctor's interference, his plan to create a clone army of himself backfired as the Doctor was in the machine beforehand, gaining his youth back. However, the Doctor, deciding that he was tired of running from his enemies, had to remove the randomiser in order to repair the machine. (TV: The Leisure Hive)

Arriving on Tigella, a planet he visited centuries earlier, the Doctor was accused of stealing the Dodecahedron, but was saved from punishment when it was discovered someone was posing as him. He discovered Meglos, last of the Zolfa-Thurans, had stolen the object to power a device that could destroy planets. The Doctor stopped Meglos by redirecting his machine's laser back at it, destroying him. While preparing to leave for a new adventure, the Doctor received a message from Gallifrey, demanding the return of Romana. (TV: Meglos)

Trapped in E-Space
While on course to Gallifrey, the TARDIS fell through a Charged Vacuum Emboitment and into a smaller pocket universe known as E-Space. Landing on Alzarius, the Doctor met the Alzarians, who were trying to repair their ship. Romana was bitten by an Alzarian spider, falling into a trance; under its control, she allowed the Marshmen to invade. However, they were driven back out by an increase of oxygen, which was poisonous to them. Studying these species' genetics, the Doctor found that the Marshmen killed the original humanoids and evolved to replace them. Creating an antidote, the Doctor cured Romana and taught the Alzarians how to pilot their ship. During this time, he met a precocious Alzarian boy named Adric, who snuck on board the TARDIS before they left to find a way back home to their universe as there was nothing left on Alzarius for him. (TV: Full Circle)

After discovering Adric had stowed aboard his TARDIS, the Doctor and Romana next arrived on the most technologically advanced planet in E-Space, where they learned of a human ship called the Hydrax that came there several years ago. They met the Three Who Rule, discovering their castle was actually the Hydrax and they were vampires, converted by the Great Vampires' king, an old nemesis of the Time Lords. During the Time of Arising, in which the King would be resurrected and return to N-Space, the Doctor launched an escape craft from the Hydrax through its heart, killing the ancient creature. After this, the Doctor set off to return Adric home, as well as to find a way back into his own universe. (TV: State of Decay)

Around the same time, the Doctor came under attack from another group of vampires and lost enough blood to put his life in danger. The Eighth Doctor, who was travelling through his past to regain his memories, gave his past incarnation a blood transfusion, saving him and ensuring that the Eighth Doctor received all his memories from his fourth life at the same time. (PROSE: The Eight Doctors)

Still in E-Space, the Doctor and his companions spent nine days in an enclosed building called the Structure and freed a system administrator called J from a creature known as "the Encroachment". (PROSE: O, Darkness)

When the TARDIS was attacked by Ballustrans, the Doctor was injured and retreated to the Zero Room in his TARDIS to recover, whilst Romana and Adric were arrested by law enforcer Marni Tellis on suspicion of twelve murders and taken to the moon of Letrus. Once he recovered, the Doctor discovered the Farrian were responsible and, alongside Marni and his companions, foiled their plot to invade E-space and open a CVE into N-space. (AUDIO: The Invasion of E-Space)

While travelling through E-Space to take Adric home, the Doctor ended up at the Gateway, a location directly between N-Space and E-Space, and time winds blew into the TARDIS, damaging K9 while he was attempting to land. While at the Gateway, the Doctor found Tharils being mistreated by a man named Rorvik in his desire to leave the limbo between realities. When Rorvik's final attempt to leave backfired, it cost him his life. Upon finding the way home, the Doctor discovered Romana wished to remain to help the Tharils. Saddened, the Doctor agreed to let her do so with K9 as a parting gift. As Adric never had any intention of returning home to Alzarius, the Doctor allowed him to stay aboard the TARDIS and return to N-Space with him. (TV: Warriors' Gate)

Return to N-Space
Back in N-Space, the Doctor was called by the Traken Union's Keeper to assist him in keeping evil away while his power waned from age, and a replacement was found. He encountered Nyssa of Traken and her father, Tremas, when he and Adric were accused of wishing to take the Source for themselves. The Doctor eventually discovered was attempting to steal the Source, planning to use its power to merge with him to get a new body. However, the Doctor turned the tables on him again, leaving the Master to perish in his exploding TARDIS. (TV: The Keeper of Traken)

After the Doctor had left K9 Mark II to Romana as a gift, he constructed K9 Mark III, who travelled with him and Adric for a short time. (PROSE: Inter-Galactic Cat, Conundrum, Planet of Paradise, Plague World, Just a Small Problem) However, after a while, the Doctor left K9 with Sarah Jane at Hill View Road in 1978 South Croydon, (TV: A Girl's Best Friend) much to Adric's dismay. (PROSE: A Boy's Tale)

Final adventures
Travelling alone to Earth during World War I to investigate a rip in the fabric of time, the Doctor discovered Lawrence Grainger, the father of his old friend, Edward Grainger, had been sent to single-handedly battle an entire Turkish hoard by time-travelling film-maker, Jack Holbine. Realising that Lawrence's death could rewrite Edward and humanity's bright future, the Doctor unwillingly joined forces with Jack to save Lawrence, ensuring Edward's future as one of history's greatest peacemakers was secured. (PROSE: Direct Action)

The Doctor met the crew of the Terrain Survey Vessel Excelsior on UX-4732 and failed to stop them from destroying a giant spider before it could hatch into a butterfly creature, (COMIC: Spider-God) then was briefly held prisoner by a psychopathic soldier who wanted to use the TARDIS as a weapon during the Millennium Wars, (COMIC: The Deal) and failed in his efforts to help the Guardian Angels escape a city populated by vicious cannibals. (COMIC: End of the Line)

When the TARDIS was picked up by the Drifter, the Doctor accidentally reactivated a Mondasian Cyberman stored aboard. When it hijacked the TARDIS and kidnapped the Drifter pilot, Jetsam, the Doctor flew the Drifter to AS4 in pursuit with the other pilot, Flotsam. They saved Jetsam, recovered the TARDIS and stopped the lone Cyberman from reactivating the Cyber-Leader, Zogron, from the ruins of a crashed Cyber-fleet. (COMIC: Junk-Yard Demon)

The Doctor re-encountered Jetsam and Flotsam on a junkyard planet called Grot and helped them to stop gun-runner Joylove McShane from reactivating and taking control of a troop of Cybermen. (COMIC: Junk-Yard Demon II)

The Doctor was contacted by Bernice Summerfield, and told that the Sirens of Time had hijacked the first Gallifreyan experiment of time travel, turning it into a time paradox that was splitting the universe apart. While the experiment had already been stopped by Leela and Romana, the Time Lords were in danger of not discovering time travel. Along with his third, fifth, sixth, seventh and eighth incarnations, the Fourth Doctor was brought to Henlen to serve as one of the six pilots needed to handle the TARDIS prototype, while his first, second and tenth incarnations stayed behind to deal with the possible backlash. The experiment was successful, restoring the correct timeline and the Fourth Doctor was taken back to his own time by Benny. (AUDIO: Collision Course)

Death
Tired of the TARDIS' chameleon circuit being stuck, the Doctor went to Logopolis to obtain the formula needed to fix it. Arriving, the Doctor found a woman named Tegan Jovanka had accidentally boarded the TARDIS during a brief trip to Earth, thinking it was a police box. He also reunited with Nyssa, whilst also meeting a being known as the Watcher; they had a secret conversation and the Doctor learnt the Watcher was a manifestation of his next incarnation and that he would be regenerating soon. Realising his end was near, the Doctor got the formulas from Logopolis and shrunk the TARDIS by accident due to 's interference, but this was corrected. The Doctor then went to the Pharos radio telescope to a broadcast the CVE signal as the Watcher took Adric and Nyssa outside the universe.

After successfully reopening the CVEs, the Doctor's short-lived alliance with the Master ended when the Doctor attempted to stop him from forcing the universe into serving the Master with the threat of weaponising the entropy. Pulling the plug on the radio that powered the dish to do so, the Doctor ended up hanging onto it as the Master rotated the dish. Dangling from the dish, the Doctor experienced visions of past foes before he lost his grip and fell to the ground.

In a daze from the fall, the Doctor experienced visions of the Brigadier, Benton, Sarah, Harry, Leela, K-9 and Romana. When Adric, Nyssa and Tegan gathered around him, the Doctor smiled, telling them that the moment had been prepared for. Shocking everyone present, the Doctor held his hand out to the Watcher, who merged with the Doctor as he regenerated into his next incarnation. (TV: Logopolis)

Post-mortem
When trapped in a dimensionally-unstable pocket universe controlled by Iam and, the Sixth Doctor's morphic print was destabilised, causing him to unwillingly regress back through his previous incarnations as his body sought a stable morphic print. (PROSE: State of Change)

In a bid to detach the Funhouse from the TARDIS in the time vortex, the Sixth Doctor binded the switch that protected the TARDIS' passengers from the changing time fields outside with a string, allowing him to pull it remotely from the limited protection of the Zero Room. As a result, the Doctor immediately began to regress back through his first five incarnations as he made his way back to the console room where, as the First Doctor, he flipped the switch back, restoring himself while trapping the Funhouse in the vortex. (COMIC: Funhouse)

When the Seventh Doctor entered his own mind to confront the Timewyrm, the Fourth Doctor appeared as a ferryman to lead the Seventh Doctor from the Third Doctor's part of the mind into the deeper subconscious to confront his foe. (PROSE: Timewyrm: Revelation)

When the Tenth Doctor was confronted by Es'Cartrss within the TARDIS' Matrix, he summoned the Fourth Doctor, among his other past incarnations, to use their united memories and willpower to take back control of the Matrix. (COMIC: The Forgotten)

During many failed attempts to duplicate the Tenth Doctor, defective copies of all his past incarnations, including the Fourth Doctor, were created instead. (COMIC: Breakfast at Tyranny's)

After the Eleventh Doctor was accused of committing deadly crimes against the Overcast, he brooded in the TARDIS for two days, imagining all his previous numbered incarnations, including the Fourth Doctor, interrogating him over the crimes. When he offered the rational that he always left things better than he found them, they all turned and left him in disgust and disgrace. (COMIC: Pull to Open)

When the Eleventh Doctor was attacked by the Then and the Now on Lujhimene, the Fourth Doctor was among the incarnations seen as the Doctor's timeline was almost destroyed. (COMIC: Running to Stay Still)

When the Eleventh Doctor entered into the T'keyn Nexus in order to defend himself, Matrix projections of his previous incarnations, including the Fourth Doctor, appeared inside it to defend themselves as well. Continuing from the Third Doctor's declaration of preventing "busybodies" from altering history, the Fourth Doctor proudly proclaimed himself a "busybody", but one who would sacrifice his life for the Earth instead of one who would rule or destroy it. When the Eleventh Doctor began to deduce Sondrah's true identity, the past Doctors faded away as Oscar Wilde interfered with the Nexus. (COMIC: Dead Man's Hand)

When Clara Oswald entered the Doctor's time stream, she saw the fourth incarnation among the Doctors that ran past her, with the Eleventh Doctor claiming them to be his "ghosts". (TV: The Name of the Doctor)

After saving Gallifrey from the Moment at the conclusion of the Last Great Time War, the Eleventh Doctor dreamed of himself standing with all his past incarnation, including the Fourth Doctor, as he thought about his search for Gallifrey. (TV: The Day of the Doctor)

While the Twelfth Doctor was on the planet Eed'n, he became infected with pollen from the plants and possessed by the entity that controlled all of Eed'n's plants, but he was able to fight off the possession by summoning the memories of his past incarnations, such as the Fourth Doctor. (COMIC: Petals)

When he was exposed to energy from a time storm, the Twelfth Doctor degenerated through all of his previous incarnations, including the Fourth Doctor. (AUDIO: The Lost Magic)

Undated adventures

 * The Fourth Doctor and Azmael had an encounter in which Azmael drank so much that the Doctor had to throw him into a pool to sober him. (TV: The Twin Dilemma)
 * The Fourth Doctor visited the Vega Station and won millions of plaudits in the casino. (PROSE: Demontage)
 * River Song met the Fourth Doctor, writing in her diary that he had a whole room just for his scarves. She had his memory wiped with mnemosine recall-wipe vapour so the timeline would remain intact. (GAME: The Eternity Clock)
 * On a Thursday in the summer of 1966, the Fourth Doctor visited Andy Warhol to have his face added to a portrait of eleven incarnations of the Doctor. (PROSE: The War of Art; COMIC: The Girl Who Loved Doctor Who)

Alternate timelines
When the Faction Paradox altered events to cause the Third Doctor to regenerate on Dust, (PROSE: Interference: The Hour of the Geek) the Fourth Doctor went on to combat the Eight Legs, (PROSE: The Blue Angel) but was only able to halt their eventual conquest of the universe. (PROSE: The Ancestor Cell)

Under the influence of the Valeyard and the Dark Matrix, the Fourth Doctor was corrupted into destroying the Daleks at their very beginning. This timeline was negated when the Seventh Doctor defeated the Valeyard and released the Dark Matrix from his control. (PROSE: Matrix)

In an alternate timeline created by the Discordia, the Doctor had a passionate romantic relationship with River Song that began in his first incarnation, having married her by his fourth incarnation. When he learned that the only way to defeat the Discordia was to dismantle his timeline, the Doctor admitted that he was afraid to lose River, but was reassured that they would meet again in another timeline. (AUDIO: Someone I Once Knew)

The Doctor and Leela met the Eighth Doctor's companion, Charley Pollard, when she appeared aboard the TARDIS. As he had detected temporal disturbances in the Time Vortex, the Fourth Doctor realised that Charley was one of his companions from the future. He later met the Eighth Doctor himself and got along well with him. He also briefly met his fifth, sixth and seventh incarnations. The Sixth Doctor was able to bring the eight versions of the Doctor together, using the dimensional stabiliser on the TARDIS owned by the Time Lord Straxus, and together the Doctors stopped the reality bomb from going off. Afterwards, the First Doctor turned off the automatic distress actions, which had brought all of the doctors to the pocket dimension and had triggered the TARDIS' destruction, making it so none of that had happened. (AUDIO: The Light at the End)

At two different points in the Doctor's fourth incarnation, one during his time traveling with Leela and another during his adventures with Romana's second incarnation, the TARDIS picked up the signal of a temporal distorsion coming from the planet Henlen, and the Doctor went to investigate. With the Doctor and Leela in a thick jungle and the Doctor and Romana in an ever-changing city, the Doctors and their companions were pursued into a refuge where they found writings in ancient Gallifreyan, and realised they were in the TARDIS prototype that was used for the first experiment of time travel by the Time Lords, and that they were being chased by the original six pilots, who explained that the experiment was sabotaged by the Sirens of Time.

They turned into the starting point of a massive temporal paradox, which was splitting reality apart, and which trapped the pilots into a time loop. They begged the Doctor to stop the experiment and kill them, but he refused. The leader then chose to have the experiment fail himself, thus causing Time Lords never to discover time travel. As a result of his choice, the Doctors, Romana and the TARDISes were erased from time, and Leela was left to die at the hands of the Sirens. However, these events were later cancelled when the paradox was resolved. (AUDIO: Collision Course)

When the Cybermen allied with Rassilon to take over history, (COMIC: Supremacy of the Cybermen) the Fourth Doctor was confronted by a cyber-converted K9 while facing the Cybermen in a mansion, (COMIC: Prologue: the Fourth Doctor) and was then ambushed by the Cybermen. (COMIC: Supremacy of the Cybermen)

While travelling in E-Space, the Doctor arrived on the planet Veridis, where scientists had created a machine that could bring the dead back to life, this discovery completely destabilising society as everyone clamored for their loved ones to be brought back from the dead. The Doctor was able to destroy the machine, but this was only possible when he and Romana sacrificed themselves to destroy it. Adric was left to make a life for himself on Veridis as the TARDIS decayed and K9 ran out of power, but when he began to experience dreams of the destruction of N-Space in the Doctor's absence, Adric developed his own time machine to go back and undo the events of the Doctor's death so that he could live to save the universe again. (AUDIO: A Full Life)

Personality
The Fourth Doctor was bohemian-like in nature and stood apart from others, even his own people. He delighted in keeping both friends and foes alike off guard with oddball humour and curious pranks, often playing the fool to lull his opponents into underestimating him, believing that there was "no point being [a] grown-up if you can't be childish sometimes". (TV: Robot, Revenge of the Cybermen, The Deadly Assassin, The Invasion of Time, The Armageddon Factor, City of Death) Although he was generally peace-loving and kind-hearted, the Doctor would react with explosive fury when provoked. (TV: Genesis of the Daleks, Planet of Evil, Pyramids of Mars, The Brain of Morbius, The Seeds of Doom, The Invasion of Time, The Pirate Planet)

The Doctor could be pedantic at times, often acting erratically in crisis, reacting to others with witty wisecracks and constantly changing his direction of speech. (TV: Robot, Genesis of the Daleks, Revenge of the Cybermen, Terror of the Zygons, Pyramids of Mars, The Brain of Morbius, The Seeds of Doom, The Face of Evil, The Talons of Weng-Chiang, The Invasion of Time, The Stones of Blood, The Armageddon Factor, Destiny of the Daleks, City of Death)

The Fourth Doctor had a consistently anti-authoritarian attitude, with little tolerance for religious dogma (TV: The Face of Evil, The Brain of Morbius, Underworld, The Stones of Blood, The Power of Kroll) or nationalism, (TV: Robot, The Armageddon Factor) but held a great respect for the White Guardian. (TV: The Ribos Operation) He generally maintained his distance from the Time Lords, and resented that they were capable of re-entering his life when they deemed it necessary. (TV: Genesis of the Daleks, The Brain of Morbius) Not only was he more inclined towards a solitary existence, (TV: The Deadly Assassin) he also emphasised his distance from humanity, (TV: Pyramids of Mars) though also stated on multiple occasions that he found mankind to be his favourite species. (TV: The Ark in Space, The Masque of Mandragora)

He was almost completely devoid of fear, reacting unfazed to threats of pain and death, (TV: The Android Invasion, The Brain of Morbius, The Seeds of Doom, The Stones of Blood, The Armageddon Factor, City of Death) and assassination attempts. (TV: The Face of Evil, The Robots of Death, The Talons of Weng-Chiang) When it seemed he was doomed, he resolved to accepting his fate, often lamenting the long life he had, (TV: The Power of Kroll) and the friends he had with him. (TV: The Horns of Nimon) However, the Doctor was afraid of losing his sanity. (PROSE: The Fear)

He refused to believe in ghosts, (AUDIO: The Foe from the Future) and admired the Peanuts comics. (PROSE: Psi-ence Fiction)

The Doctor had a liking for tigers, (AUDIO: The Circus of Doom) butlers, (AUDIO: Destination: Nerva) badgers, (AUDIO: The Sands of Life) and cows. (PROSE: Psi-ence Fiction)

He liked to drink ginger beer (TV: The Android Invasion) and lemonade, (PROSE: Eye of Heaven) and eat doughnuts, (AUDIO:  The Beautiful People) and kebab. (PROSE: The Brain of Socrates) Aside from jelly babies, he also liked aniseed balls and humbugs, (AUDIO: The Circus of Doom) but disliked celery. (AUDIO:  The Beautiful People)

He disliked having to move people around in the TARDIS, (AUDIO: A Shard of Ice) swimming, (PROSE: Last Man Running) not being in control of his situation, (PROSE: Match of the Day) and tour guides. (PROSE: Scarab of Death)

Despite his charm and offbeat humour, the Fourth Doctor could be intensely brooding, serious and even callous at times, (TV: Pyramids of Mars, The Seeds of Doom, The Invasion of Time, Logopolis) and would keenly scrutinise his surroundings even when playing the fool. When Sarah upbraided him over his callousness at the sight of Laurence Scarman being killed by the animated corpse of his own brother, the Doctor reminded her of the larger issue of stopping Sutekh. (TV: Pyramids of Mars) He would be furious with those he saw as stupid, frivolous, misguided, or evil. (TV: The Face of Evil, The Robots of Death, Nightmare of Eden) When taking charge, he was authoritative to the point of egocentricity, though he eventually proved himself as the only one capable of solving the situations he found himself in. (TV: Revenge of the Cybermen, The Armageddon Factor)

He was also not against taking a life in extreme circumstances, (TV: The Brain of Morbius, The Invasion of Time) but would scold Leela for unnecessary killing. (TV: The Face of Evil) Though he was much less inclined to use physical violence than his predecessor, the Fourth Doctor would react aggressively if he had no alternative but to defend himself. (TV: Planet of Evil, The Seeds of Doom) He improvised non-lethal weaponry when necessary, (TV: Planet of Evil) but was also willing to use more lethal weaponry, like the De-mat Gun and Earth firearms, if necessary. (TV: The Seeds of Doom, The Talons of Weng-Chiang, Image of the Fendahl, The Invasion of Time)

He threatened to deactivate Davros' life-support machine to coerce him into destroying the Daleks, (TV: Genesis of the Daleks) fatally electrocuted an attacking Tesh under Xoanon's control, (TV: The Face of Evil) and seemed to have nothing against Leela killing random attackers, as long as she kept quiet about it. (TV: The Talons of Weng-Chiang) He was also willing to sacrifice himself in order to kill Davros via an explosive device in an attempt to prevent the Daleks harnessing their creator. (TV: Destiny of the Daleks)

Nevertheless, the Doctor still had a strong moral code, such as confronting J.P. Kettlewell about how the ends never justified the means, (TV: Robot) and when he faced the dilemma of whether to destroy the Daleks, stating that if he did, he would be no better himself than the Daleks. (TV: Genesis of the Daleks) He was also appalled at the actions of the Captain, (TV: The Pirate Planet) and refused to listen to Professor Tryst's attempts to justify drug-running in order to fund his scientific work, simply telling him to go away. (TV: Nightmare of Eden) He also attempted to save Harrison Chase from death, despite Chase previously attempting to kill him. (TV: The Seeds of Doom)

The Doctor was not above the occasional act of hypocrisy, telling Harry Sullivan that it was a waste to throw something away, immediately before disregarding a piece of metal that had saved his life. He also told Harry it was "a mistake to clutter one's pockets", despite he himself keeping a large variety of things in his own pockets. (TV: The Sontaran Experiment) He later berated Romana for assuming the worst, and then stated himself that things usually were at their worst, (TV: The Armageddon Factor) and took a liking to her second incarnation when she mimicked his dress sense, despite previously telling her that "external appearances weren't important". (TV: Destiny of the Daleks) He was also unwilling to admit to any wrongdoing on his part. (TV: The Sun Makers)

He was also not averse to winding up his companions on occasion, such as questioning Sarah Jane's integrity to encourage her to manoeuvre herself out of a ventilation shaft. (TV: The Ark in Space) He later fooled Leela into playing with a yo-yo for an extended period of time, with her believing it was a form of magic. (TV: The Robots of Death) On another occasion, he caused Romana to panic when he pretended to be corrupted by the Key to Time. (TV: The Armageddon Factor)

The Fourth thought his third incarnation was "arrogant", (PROSE: Old Flames) and an "incorrigible show-off". (PROSE: Categorical Imperative)

When he came across a statue of the Eleventh Doctor, the Fourth Doctor criticised his future self's nose and bow tie, and also expressed shock of his use of the word "cool." (PROSE: The Roots of Evil) However, when he met his eleventh incarnation in person, he found that he got along well with him, (AUDIO: Babblesphere) and also easily cooperated with the Eighth Doctor. (AUDIO: The Light at the End)

While the Fifth Doctor thought of his fourth incarnation as "a careless freewheeler who thought he was invincible", (AUDIO: Excelis Dawns) the Eighth Doctor remembered his fourth incarnation as a "casual bohemian" who "dared to take on the evil that stalk[ed] the dark". (PROSE: The Eight Doctors)

Unlike his other incarnations, the Fourth Doctor would rarely invite others to travel with him, a majority of his companions inviting themselves aboard the TARDIS, (TV: Robot, The Face of Evil, Full Circle) or having someone else persuade the Doctor to let them join him. (TV: The Invisible Enemy, The Ribos Operation, Logopolis) Nevertheless, the Doctor had a close friendship with his companions, and worried about their safety. (TV: The Hand of Fear) He considered Sarah Jane Smith, Leela and K9 Mark I and Mark II to be his best friends. (TV: The Seeds of Doom, The Invasion of Time, The Pirate Planet) However, he viewed Harry Sullivan as an imbecile, (TV: Revenge of the Cybermen) and believed that any intelligence that Harry showed was due to his influence. (TV: The Ark in Space)

Younger in appearance than his previous incarnations, the Fourth Doctor found himself drawing closer to his companions than he might have previously. (TV: School Reunion) He tended not to display such feelings himself, not even when accompanied by the often scantily clad Leela, (TV: The Robots of Death) although he acknowledged that Romana was attractive in her first incarnation, (TV: The Pirate Planet) and, in her second incarnation, he even kissed her. (PROSE: The Well-Mannered War) The Doctor felt a close connection with Romana, due to her being a Time Lord with ideas like his, and was even tempted to cease travelling to be with her. (PROSE: Notre Dame du Temps) He was, for the most part, oblivious to other people's attractiveness, believing that telling Countess Scarlioni that she was "probably beautiful" was a compliment. (TV: City of Death)

Unlike his predecessors, the Fourth Doctor did not maintain a close working relationship with UNIT, reacting with anger and disdain when he was recalled back to Earth by the Brigadier. (TV: Terror of the Zygons, Pyramids of Mars) Except for a handful of occasions, the Doctor kept his distance from the organisation. (TV: Robot, Terror of the Zygons, The Android Invasion, The Seeds of Doom)

In her first incarnation, Romana stated that the Doctor was "capricious, arrogant, self-opinionated, irrational, and [didn't] even know where [he was] going", (TV: The Armageddon Factor) while her second incarnation would admit in private that he was an " incredibly resourceful and intelligent person". (PROSE: The Well-Mannered War) Adric described the Fourth Doctor as "unpredictable, intimidating and enigmatic, but brilliant". (AUDIO: Psychodrome) The Sisterhood of Karn remembered the Fourth Doctor as a "prattling man full of idle questions". (AUDIO: Sisters of the Flame)

When the Eighth Doctor had a tarot card reading, the Fourth Doctor was identified as "the Fool". (PROSE: The City of the Dead)

After seeing himself being observed by the Watcher, the Doctor became aware his end was nearing, adopting a resigned mood while vowing to stop, eventually losing the strength to keep his grip on the Pharos Project radio telescope's gantry, and fell to his death. As he lay dying, the Doctor spent his last moments thinking of his past companions, and then explained to his present friends that the moment of his regeneration had been prepared for, with a serene glance and a final grin. (TV: Logopolis)

Habits and quirks
The Fourth Doctor would often have jelly babies with him and offered them as a greeting. (TV: Robot, The Ark in Space, The Face of Evil, The Robots of Death, The Talons of Weng-Chiang, Image of the Fendahl, The Sun Makers, The Invasion of Time, Destiny of the Daleks, The Horns of Nimon) While past and future incarnations also showed occasional fondness for the sweet, (TV: The Dominators, The Three Doctors, The Mysterious Planet, Doctor Who, Mummy on the Orient Express) theirs was never as frequent as the Fourth Doctor's love for them. (AUDIO: Death-Dealer) His favoured choice was the orange coloured jelly babies. (TV: The Invasion of Time)

He would often instruct his companions to follow him by saying, "Come on", even saying it when he was following them. (TV: The Ark in Space, The Hand of Fear, The Talons of Weng-Chiang, The Ribos Operation, Destiny of the Daleks, City of Death) He would often ask others if they were listening to him, (TV: The Armageddon Factor) and often told K9 to "shut up". (TV: The Stones of Blood, The Armageddon Factor, Destiny of the Daleks) In the later parts of his life, the Doctor would stretch the last syllable of "Hello" when greeting himself.

He often talked to himself, with Sarah Jane Smith stating he did so "mostly because [he was] the only person who [knew] what [he was] talking about", (TV: The Ark in Space, The Invasion of Time) and would often describe an inhumane adversary as an "unspeakable abomination". (TV: The Sontaran Experiment, The Brain of Morbius)

The Fourth Doctor was prone to flashing his upper teeth when grinning. (TV: Robot, The Sontaran Experiment, Revenge of the Cybermen, Terror of the Zygons, The Masque of Mandragora, The Robots of Death, The Sun Makers, The Invasion of Time, The Ribos Operation, City of Death, Logopolis)

When relaxing, the Doctor tended to put his foot up on a ledge and lean back, often placing his hat over his face as he slept. (TV: The Androids of Tara) To allure a sense of mystery, the Doctor would often tap his nose when keeping secrets. (TV: Robot, The Brain of Morbius, The Creature from the Pit)

He would play with a yo-yo to relax. (TV: The Ark in Space, The Android Invasion, The Brain of Morbius, The Seeds of Doom) He also started a trend of talking to the TARDIS, (TV: The Deadly Assassin, The Horns of Nimon) constantly showing affection for his magnificent machine by kissing it and caring for it when it got damaged. (TV: The Invasion of Time, The Ribos Operation)

According to one account, the Fourth Doctor always carried a piccolo on his person, telling Sarah that he "always played the piccolo when [he was] nervous" to "relieve the tension". (AUDIO: Doctor Who and the Pescatons)

Skills
Much like his immediate predecessor, the Fourth Doctor was very physical, being an excellent runner and fighter, (TV: The Sontaran Experiment, Genesis of the Daleks, Planet of Evil, The Android Invasion, The Deadly Assassin, The Face of Evil, The Talons of Weng-Chiang, City of Death, The Keeper of Traken) capable of withstanding levels of pain that would normally kill a human. (PROSE: The Romance of Crime) He was also shown to be a highly skilled swordsman, being able to hold his own against multiple opponents, (TV: The Masque of Mandragora) and the finest swordsman on Tara. (TV: The Androids of Tara)

Showing incredible accuracy, the Doctor was able to hit a bullseye on a dart board, (TV: The Android Invasion) strike a strand of rope with a crossbow, (TV: The Face of Evil) and throw an axe at Magnus Greel's distillation machine to free Leela. (TV: The Talons of Weng-Chiang)

The Doctor possessed telepathic powers, allowing him to communicate with other telepathic users. While other incarnations had to make physical contact to use telepathy, the Fourth Doctor could project his mind over long distances. This also allowed him to guide the Mentiads into using their telekinetic powers to move a spanner in order to ruin the plans of the Captain and Xanxia. (TV: The Pirate Planet) Due to, what he described as, his complex mind, (TV: The Invasion of Time) the Doctor was able to immunise himself from telepaths, such as Li H'sen Chang, (TV: The Talons of Weng-Chiang) and the Vardans. (TV: The Invasion of Time)

The Doctor also claimed to be a master hypnotist, hypnotising Sarah Jane simply by laying his hands on her temples. (TV: Terror of the Zygons, The Hand of Fear) Other times, the Doctor would instead use a fob watch to hypnotise someone, (TV: The Ribos Operation) or break another hypnotists hold on them. (TV: The Talons of Weng-Chiang) He was also able to use vocal commands to free Leela from Xoanon's mental control, (TV: The Face of Evil) and to hypnotise Rodan into assisting K9 in constructing the De-mat Gun, and then break her hypnosis with the snap of his fingers. (TV: The Invasion of Time)

He could check a pulse with his knee. (PROSE: The English Way of Death)

The Doctor could read with incredible speed, detect the level of immuno-agents in blood by its smell, (PROSE: The English Way of Death) and see through cloaking-fields. (PROSE: Managra)

The Doctor admitted to Sarah Jane that, if he really wanted to, he could easily control the destination his TARDIS took, but that he preferred to only do so in moments of importance. (PROSE: Evolution)

He could commandeer and ride a horse with ease. (TV: The Masque of Mandragora)

The Doctor could speak Mandarin and Cantonese, among other dialects, (TV: The Talons of Weng-Chiang) such as Swahili. (AUDIO: Trail of the White Worm)

Like several of his incarnations, his pockets appeared to be dimensionally transcendental, as he carried a large array of items in his pockets, which included a seemingly endless supply of Jelly babies, a galactic passport, (TV: Robot) a cricket ball, (TV: The Ark in Space) a magnifying glass, gemstones, handcuffs, an etheric beam locator, (TV: Genesis of the Daleks) a lockpick, (TV: Pyramids of Mars) a football rattle, (TV: The Masque of Mandragora) a magician's cane, (TV: The Hand of Fear) a clockwork egg-timer, (TV: The Face of Evil) a breathing tube, (TV: The Robots of Death) a yo-yo, a toy Batmobile, a stuffed mouse, (TV: The Talons of Weng-Chiang) a barrister's wig, (TV: The Stones of Blood) and an instant camera. (TV: City of Death) On one occasion, he even dropped a cup containing a hot beverage into his pocket. (TV: The Power of Kroll)

The Doctor could also perform magic tricks, (TV: The Talons of Weng-Chiang) write decryption algorithms for computers, (PROSE: System Shock) play poker, (PROSE: The Drosten's Curse) and judge character keenly, almost instantly knowing whom to trust. (TV: The Ribos Operation)

Appearance
Standing at 6'4", (PROSE: The Romance of Crime) the Fourth Doctor was notable for having large, expressive blue eyes, a large hooked nose, a round chin, bright white teeth and a large head of wild curly brown hair, (TV: Planet of the Spiders, Robot) leading him to frequently be described as being "all teeth and curls". (TV: The Five Doctors; WC: Shada; PROSE: The Touch of the Nurazh; COMIC: The Lost Dimension)

Upon first seeing his reflection, the Doctor thought his "nose [was] a definite improvement" over his predecessor's, but was unsure about his ears in comparison. (TV: Robot) He also thought himself as being attractive. (AUDIO: The Power of the Daleks)

Li H'sen Chang described the Fourth Doctor as "tall with wide pale eyes and hair that curls like the ram." (TV: The Talons of Weng-Chiang)

The First Doctor described his fourth incarnation as the "taller chap with the teeth and the scarf", (PROSE: Five Card Draw) while the Sixth Doctor called him the "tall one with the teeth and the dark mass of curly hair". (PROSE: The Shadow in the Glass)

When Affinity took on the Fourth Doctor's appearance, the Twelfth Doctor noted that his fourth incarnation's "eyes bulged alarmingly above tombstone teeth". He also doubted that the "battered hat jammed down over a madness of brown curls and an improbably long scarf displayed any sort of style." (PROSE: Silhouette)

Main attires
In stark contrast to the elegant and refined figure of his previous incarnation, the Fourth Doctor was an unkempt, bohemian-looking figure, with his most distinctive item of clothing being an extremely long, multi-coloured scarf, (TV: Robot) which had originally been knitted for him by Madame Nostradamus. (TV: The Ark in Space) His dark curly hair was often partially hidden by a floppy brown fedora. (TV: Robot)

Aside from his scarf, the Doctor's first outfit consisted of a rust-brown corduroy blazer with elbow patches, baggy grey tweed trousers, a dark brown cardigan with diamond shapes adorning the front, a white dress shirt, a long green neck-tie, and ankle-high leather shoes. (TV: Robot)

Eventually, his style stabilised into a frock coat, trousers, and some form of a cravat or tie with waistcoat, fedora, and his scarf. (TV: Pyramids of Mars) He later abandoned neck wear in favour of an open-necked shirt, with a likewise unbuttoned waistcoat. (TV: Underworld) He also varied his footwear to include knee-high leather boots. (TV: The Deadly Assassin)

He wore several frock coats of different colours, including a dark brown one, (TV: Pyramids of Mars) and a light grey one. (TV: The Brain of Morbius) He sometimes adorned his coats with lapel pins and brooches in various shapes, such as a flock of geese, (TV: The Power of Kroll) or an artist's pallet with tubes of paint. (TV: City of Death) He occasionally wore trench coats as well, including a light brown one with dark brown trim, (TV: The Power of Kroll) and a plum velvet one. (TV: The Leisure Hive)

Toward the end of his life, however, the Doctor's costume and his colour palate shifted to a darker red colour scheme. (PROSE: Into the Silent Land) This consisted of a completely new scarf, along with a full-length maroon coat, waistcoat, trousers, buccaneer-style leather boots, a Poet's Hat, an ecru open-neck dress shirt with subtle ecru question marks adorning the collars. (TV: The Leisure Hive)

Professor Frederick Marius remarked that the Doctor looked like a "space vagrant". (TV: The Invisible Enemy)

Age
While on Earth, the Doctor stated his age to be 749 years. (TV: The Seeds of Doom) After ageing four years from crossing a split in time, the Doctor said he would "still think of myself as 743", before admitting he "could never remember" his age. (COMIC: Doctor Who and the Time Witch) He was approximately 813 when he regenerated into his fifth incarnation. (PROSE: Cold Fusion)

Casting
Actors considered for the role of the fourth incarnation included Michael Bentine, Bernard Cribbins, Graham Crowden, Fulton Mackay and Jim Dale. Tom Baker was cast based on his role as the villain Koura in.

Appearance
According to the creators of the show and Baker, the character's look was originally based on paintings and posters by Henri de Toulouse-Lautrec of his friend, Aristide Bruant, a singer and nightclub owner whose trademark was a black cloak and long red scarf.

Possible romances
Since the fourth incarnation was the youngest in appearance at the time, he therefore appeared closer in age to his companions. This led to concerns being expressed of possible "hanky panky in the TARDIS", a term often used in the tabloid press to suggest the impression of off-screen dalliances between the various Doctors and their young, female companions.

Perhaps to address this, according to the Information Text commentary on the 2007 DVD release of The Stones of Blood, Baker generally tried to emphasise the asexuality of the character, apart from possible subtle romantic tension such as that with Sarah Jane Smith. Despite this, Baker was not above tossing in occasional visual jokes that suggested sexual tension.

For example, in The Stones of Blood the Doctor and Romana have to huddle close in order to be within the confines of a transporter beam and enter what would, in normal circumstances, be seen as a romantic clinch, but neither character appears to recognise this. Likewise, the Doctor and Romana are forced into close proximity in The Ribos Operation when hiding from Graff Vynda-K and neither seem to recognise this as a romantic moment.

Secondary media, on the other hand, has often restrained less from romantic moments; particularly with Romana II. For instance, in the Short Trips story Special Occasions: 2. Do You Love Anyone Enough?, the Doctor gave Romana the last Rolo in the Universe for St Valentine's Day. In PROSE: The Well-Mannered War, the Doctor kissed Romana on the cheek.

In popular culture
The fourth incarnation's distinctive appearance and mannerisms have made him a target for affectionate parody. The character appeared several times on The Simpsons and twice on. Even in 2011, a full 30 years after he left his tenure as the Doctor, an animated parody of his incarnation appeared an episode of. In Hugo 2: Whodunnit?, a computer game, the player's character can save Tom Baker's Doctor from a Dalek, who in return gives the player his sonic screwdriver.

He was frequently impersonated by impressionist Jon Culshaw on the radio and television series. Even had an episode featuring an eccentric man claiming to be a time-traveller and wearing a long striped scarf. Archival footage of the fourth incarnation's first title sequence was also used in the episode "Blue Harvest" to represent and parody Star Wars' hyperspace.

Tom Baker, as the narrator of the series, has referenced Doctor Who. He also appeared in Doctor Who and the Daleks in Seven Keys to Doomsday, a stage play that opened two weeks before Baker began his tenure as the Doctor. In the play, Trevor Martin plays an alternative version of the fourth incarnation.

In the book, there was a scene in which a bunny sits on top of the TARDIS with a noose around its neck as the fourth incarnation runs into it, being chased by a Dalek.

Peter Jackson wore a costume similar to the fourth incarnation's when he played Derek in his film Bad Taste.

On, in the episode, "The Justice League Recombination", Stuart wears the Fourth Doctor's costume to a New Year's Eve costume party at his comic book shop.

The video game Team Fortress 2 features the Fourth Doctor's scarf and hat as cosmetics for the Medic class. The items were renamed as the Chronoscarf and Das Ubersternmann. The hat was the first item added in the game in a 2013 patch while the scarf was not added until a year later in the 18 June 2014 update.

Reprising the role
Unlike his predecessors Patrick Troughton and Jon Pertwee or his successors Peter Davison, Colin Baker, Sylvester McCoy and Paul McGann, Tom Baker was notoriously hesitant to reprise the role of the Doctor. Originally intended as a major player in the 20th-anniversary special, The Five Doctors, Baker pulled out before production began, citing other obligations as his reasoning. The production team rewrote the scripts to give much of his role to the Fifth Doctor, and included the Fourth Doctor by making use of unbroadcast footage from Shada. A Madame Tussauds wax mannequin of his incarnation was used in publicity shots to keep the "five Doctors" concept afloat.

In 1993, Baker was hired to play the Doctor full-on for the planned 30th Anniversary Special The Dark Dimension, but the special was cancelled and instead shot a small cameo for Dimensions in Time. Around this time, he also introduced a VHS reconstruction of Shada, though not apparently in character as the Doctor. In 1997 he returned to the role in a more serious manner in the video game Destiny of the Doctors and in a Superannuation advertisement. He also appeared as Tom Baker as Fourth Doctor in the comedy docudrama Who on Earth is Tom Baker.

Despite his hesitancy to play the role again, Baker made frequent appearances on DVD releases of his stories, recording audio commentaries for many and conducting on-camera interviews for others.

In the 2000s, Baker made a tentative step towards reprising the role by agreeing to record audio books for BBC Audio, reading the texts from several Target novelisations from his era. Finally, in 2009, Baker agreed to return to the role of the Doctor in a dramatic context, performing the five-part Hornets' Nest story arc, again for BBC Audio, in which he was paired up with Richard Franklin, reprising the Pertwee-era companion Mike Yates.

In March 2010, Baker announced on his official website that he was in discussions with Big Finish Productions to record Doctor Who audio dramas for the company. Big Finish confirmed this on 3 June 2010. A few days later it was also confirmed that Baker would be doing additional stories for BBC Audio, AUDIO: Demon Quest, released at end of 2010.

Prior to the cancellation of The Sarah Jane Adventures following the death of Elisabeth Sladen, Tom Baker was briefly considered to play a role in the series, specifically in a planned 2011 Christmas special entitled Miracle on Bannerman Road, in which he would portray a mysterious traveller. (DWMSE 32)

In 2013, Tom Baker made a cameo appearance in the 50th anniversary story, The Day of the Doctor, as the curator of the National Gallery.

Other matters
From a real world perspective, the Fourth Doctor was the first incarnation to ever face a form of time war in any Doctor Who media, in the DWM comic stories The Deal and The Neutron Knights. However, this only became clear in retrospect following the Fifth Doctor's clash with the Millennium Wars in The Tides of Time.

Narratively, the Fourth Doctor is also one of the few incarnations besides the Eighth who has encountered the mythology of the War in Heaven. However, these encounters are not original stories focused on him, but instead recontextualisations of certain serials within various stories of the Faction Paradox series. Pyramids of Mars, The Brain of Morbius, The Talons of Weng-Chiang, and Image of the Fendahl all became direct aftermaths of War-or War-preparation- events. The DWM comic Doctor Who and the Iron Legion is also strongly implied to be connected to Warlords of Utopia.