Fourth Doctor

The Fourth Doctor was the fourth incarnation of the Time Lord known as the Doctor. He left all ties of his previous incarnation's exile behind on Earth, setting off to travel the cosmos. He 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 that time.

After leaving Gallifrey, 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, 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 a newly-regenerated Romana went on the run from the Black Guardian. They accidentally passed into the smaller universe of E-Space.

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

Premature Debut
The Third Doctor first regenerated after he fell off a roof during a struggle. The Nurazh attempted to take over the Doctor's mind, but, unable to cope with two different versions of the Time Lord's mind at the same time, perished, thus 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)

Post-regeneration
The Doctor's third incarnation regenerated some time after the radiation from the Great One's lair took effect upon him. He returned to Earth to end his time in the company of Sarah Jane and the Brigadier, after being lost in the Time Vortex for an unknown amount of time. K'anpo Rimpoche arrived and gave the Doctor a "push" for his regeneration. (TV: Planet of the Spiders)

Once he had regenerated, the Doctor suffered delirium, mumbling random things from his adventures, and was physically exhausted. He was put in sickbay, where Harry Sullivan kept watch on him. However, the Doctor managed to outwit him and get to the TARDIS to try to leave. Though he still had issues with situational awareness, the Doctor was asked by the Brigadier to help deal with 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 took Sarah Jane Smith and Harry Sullivan to travel with him in the TARDIS. (TV: Robot)

Adventures with Sarah Jane and Harry Sullivan
The Doctor's first trip with his companions was intended to be a quick trip to the Moon. However, due to Harry messing around with the console controls, 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. Luckily, Noah, a human converted in a Wirrn, retained his humanity 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. (TV: The Ark in Space)

Sontaran Experiments
Once on Earth, they found the Sontaran Styre there conducting experiments on humans as a prelude to an invasion. The Doctor defeated his plans, allowing the resettlement of Earth to proceed. The Doctor and his companions transmatted back to the space station to retrieve the TARDIS. (TV: The Sontaran Experiment)

Mission to Skaro, meeting Davros and Cybermen return
Intercepting their transmat beam, a Time Lord appeared to the Doctor and forced him to undertake a mission on their behalf: intervene in the creation of the Daleks. He had forseen a future where the Daleks would destroy all life in the cosmos. The Doctor was either to prevent their creation completely or induce the Daleks to develop into less dangerous creatures. Upon his arrival on Skaro, the Doctor was caught up in a war between the Kaleds and Thals, being taken prisoner by the former. While being questioned, the Doctor learned of and met the creator of the Daleks, a mad but intelligent scientist named Davros. 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. Escaping, the Doctor destroyed Davros' recording of the foreknowledge, thus keeping the future from changing for the worse. Fleeing after the Daleks turned on Davros, the Doctor buried them and their factory underground, delaying their progression by 100 years; he also tricked them into setting off an explosion, destroying their embryos. The Doctor explained to Harry and Sarah that out of the Daleks' evil came many good things; if the Daleks ceased to exist completely, worlds on good terms with each other because of alliances against the Daleks would never happen. (TV: Genesis of the Daleks)

Using a Time Ring that the Time Lords gave him, 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, miscroscopic psychiatrists and ghosts. (PROSE: The Last Thing You Ever See)

Finally reaching Space Station Nerva, the Doctor, Harry, and Sarah Jane found their arrival on the station was earlier in its time line, when it orbited Jupiter. 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. The Doctor ultimately stopped them from blowing up the planet, defeating them once more. He also saved Sarah Jane from dying of a poisonous bite from a new variety of Cybermat. Finally reunited with his beloved TARDIS, the Doctor set off for new adventures with his two companions. (TV: Revenge of the Cybermen)

Travelling by TARDIS once again
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)

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 Sinton's 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)

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. (COMIC: Avast There!)

The Doctor next took Sarah and Harry to 24th century Prague, where they visited a museum and discovered a dead body in one of the exhibts. 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)

Soon after, the Doctor, Sarah, Harry and Professor Vittorio Levi were taken prisoner on Aquatica by the Medusians, who wanted the TARDIS. Escaping, the Doctor and his trio of friends met the Phyllosians, the sworn enemy of the Medusian and their kingdom's rival. 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 accidentally landed the TARDIS in a swamp on Diamedes, where he meet the gentle, dim-witted Slodes and saved them from swamp creatures. He also reunited with a dying old friend, Zyphos, captain of the Tandrain, and offered to take him to his homeworld so that he could die peacefully and happy. (PROSE: Detour to Diamedes)

Trapped on the moon of Axa, the Doctor's body was stolen by Rascla, the twisted master of the planet Torm. Rascla intended to unleash a virus onto Miltra B, which would leave it's galaxy vunerable for his invasion force to attack. Whilst Rascle 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 endures a brutal psychic duel with Rascla. Rascle's spirit was destroyed, so the Doctor reclaimed his body and made sure Miltra B's galaxy was protected. (COMIC: The Body Snatcher)

The Doctor next travelled to a living planet and encountered giant spiders, (COMIC: The Psychic Jungle), He also visited Neuronic space and saved his friends from energy-drainer, Skizos, (COMIC: Neuronic Nightmare), defeated the reptilian Zanons on Zoto in the 41st century. (PROSE: Cyclone Terror), investigated a Time Cube called "Crystal Z" in the American desert. (PROSE: Time Snatch), and saved a group of charming cats in the Psykos system from an invasion force. (PROSE: Menace on Metalupiter)

Much to his great annoyance, the Doctor received a call for help from the Brigadier via a space-time telegraph. Upon arrival, the Doctor discovered that an alien race known as the Zygons were planning to use the Loch Ness Monster in their scheme. Upon their defeat, the Doctor decided to use the TARDIS to get to UNIT HQ quicker The Doctor and Sarah bade farewell to Harry, who wished to use a more conventional means of transportation. (TV: Terror of the Zygons)

Walking in Eternity
Predictably, the Doctor failed to pilot the TARDIS back to UNIT headquarters on present day Earth. Instead, he and Sarah Jane ended up on a planet in the far future, where they encountered anti-matter monsters. (TV: Planet of Evil)

Again attempting to return to UNIT, the Doctor instead arrived at the right location in the wrong year, 1911. There he had to prevent the last of the Osirians, Sutekh, from escaping his prison in one of the Great Pyramids and destroying the Universe. Though unsuccessful in stopping Sutekh's release and his resulting travel to Mars, the Doctor was able to delay his teleportation to Earth for (an accelerated) 4000 years, thus aging him to death. The Doctor had also expressed at this time his displeasure of working for UNIT to Sarah Jane, who advised him to resign from his position as their unpaid scientific advisor. (TV: Pyramids of Mars)

Arriving next during the right time (but not at UNIT HQ), 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; they even created an android copy of Sarah. Discovering his companion had been replaced (due to her not minding Ginger beer, something Sarah disliked), 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, including John Benton and Harry himself. (TV: The Android Invasion)

The Doctor next found his TARDIS forced to land on Karn by the Time Lords. He was angered because they were once again using him as their agent of intervention; they didn't wish to get personaly involved. There, he was tasked with preventing the Frankenstein-esque resurrection of the evil Time Lord Morbius. Defeating him in litteral battle of the minds, the Doctor managed to reduce Morbius to a instinctive beast that tumbled off a cliff to his second death. However, victory came at a heavy cost; he was on the verge of death, and it seemed he could not regenerate this time. The Sisterhood of Karn used the Elixir of Life to heal him at the cost of one of their own to the fire that made the elixir. (TV: The Brain of Morbius)

Attending another UNIT christmas party, the Doctor was unable to prevent a Voddod ship from crashing to Earth - and into UNIT HQ. 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 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)

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

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)

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

Visiting Chase Manor, The Doctor and Sarah encountered the plant-like Krynoids, who had taken control of the body of an unfortunate human, planning to spread their seeds to take over Earth. The Doctor was able to stop them thanks to the help of UNIT once more. (TV: The Seeds of Doom)

Severing the final tie
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. He also reuinted with Harry Sullivan during this adventure.(PROSE: System Shock)

Receiving another summoning from the Brigadier, the Doctor was forced to assist UNIT by investigating alien activities in the Channel Island. This adventure fuelled the Doctor's determination to cut all ties with UNIT, quickly escaping after the investigation was complete. (PROSE: Hello Goodbye)

During a trip in space, the Doctor accidentally brought 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 into using all his energy until he vanished. Using his mask and cloak, the Doctor masqueraded as him and used a device to drain the energy out of the rest of the Brotherhood, killing them and saving the Earth.

While showing off some of the rooms located deeper in the TARDIS to Sarah Jane, the Doctor discovered one of many previously used secondary control rooms his time machine had (and had apparently been used by his second and third incarnations), deciding to use it for a while. (TV: The Masque of Mandragora)

On Calderon IV, the Doctor became the target of a revenge attack by a bitter old man whom he opposed in his third incarnation. But once again, he managed to defeat him and his army of androids. (PROSE: The Android Maker of Calderon IV)

Whilst sleeping in the TARDIS, the Doctor became trapped in a dreamscape with a servant of the "Master of the Blackhole", which nearly destroyed his mind completely. (COMIC: ''Master of the Blackhole')

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. (PROSE: Jackals of Space)

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)

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)

Later, the Doctor and Sarah Jane ended up in a quarry, where an explosion nearly cost Sarah her life. The Doctor found she had obtained a petrified hand in the rubble and was possessed by Eldrad, who forced Sarah to take it to a nuclear power station. There, it regenerated into a female rock-based humanoid modelled on Sarah. The Doctor complied with Eldrad's request to be taken back to Kastria, where Eldrad's true male form was restored. It was revealed that Eldrad had gone insane and caused the end of his species; with his people extinct, he planned to rule Earth, but the Doctor managed to trip him into a pit.

While preparing to leave for new adventures, the Doctor received a telepathic summons from Gallifrey and was forced to leave Sarah behind as humans were not allowed. When returning Sarah to Earth, he "blew it," accidentally not leaving her in her home town of South Croydon. (TV: The Hand of Fear) He later learned that he had left her in Aberdeen. (TV: School Reunion)

Return to Gallifrey
Upon return to Gallifrey, the Doctor tried to prevent the death of the Lord President, but was unsuccessful, ending up getting the blame instead for his murder. The Doctor put off execution by announcing his own candidacy for Lord President, buying him enough time to discover that was responsible. Defeating the Master, the Doctor left his former teacher Borusa in charge. Throughout the adventure, he also re-experienced, to his disgust, the decadence of Time Lord civilisation. (TV: The Deadly Assassin) He also was still eligible to gain the title of Lord President even after leaving, as he was the only candidate left. (TV: The Invasion of Time)

Time alone
Deciding it was best not to return to Earth for Sarah Jane, the Doctor began travelling alone.

The Doctor arrived on Aprilia III in a parallel dimension, where he met Captain James T. Kirk, Spock, 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. The alien equipment which the archaeologists were investigating appeared dormant, but it was not.

However, seven regenerations later, these memories would come back to the Doctor when he accidently landed on the Enterprise years later in that world's timeline with Amy and Rory. He would soon realise that these new memories meant that the Cybermen were changing history. (COMIC: Assimilation²)

Arriving in 1990s Toyko 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)

Soon after, the Doctor attended a party organised by his first incarnation, along with his past two and four future incarnations. (PROSE: The Feast of Seven... Eight (and Nine))

He next travelled to 16th century America and was hailed as a god by Taric, high priest of the Mandrans. (COMIC: The Sky Warrior)

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

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 of Samarkand was plotting to marry Al's lover, and trapped him in a World of Shadows. (PROSE: The Nobility of Faith)

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)

Summoned to Earth by Brigadier-Lethbridge Stewart's recall device, the irritated Doctor discovered UNIT was facing closure. He and the Brigadier attend a court hearing in New York to save the organisation. But the Doctor was sidetracked 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 succesfully secured a bright future for UNIT and the Brigadier. (PROSE: UNITed We Fall)

Along with his first three and his four future incarnations, the Doctor saved Princess Clio of Dolmara from Malvek, a ruthless ambassador who was next in line for the throne if Clio died. After he was defeated, the Doctor attended Clio fifth's birthday party and bought her a bag of jelly babies as a present. (PROSE: The Glass Princess)

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

Once again, the Doctor was called back to UNIT. Arriving, he was reunited with Harry Sullivan and worked alongside him to return a peaceful alien home. But his plans were opposed by ruthless UNIT colonel, Dennis Horsely, who believed that the creature should be killed and experimented on. The Doctor and Harry prevented Horsely from capturing the alien and successfully returned it home. (PROSE: Mutiny)

The Doctor visited a planet colonised by the Mordee expedition, and encountered the colony ship's powerful computer, Xoanon, which he repaired from damage it sustained. He inadvertently accidentally imprinted his own mind on the computer, leaving it with multiple personalities, which lead to disatorous resaults in the following decades. (TV: The Face of Evil)

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)

A noble savage
The Doctor returned to the planet colonised by the Mordee centuries before, where he found that he was remembered as an evil god 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. After the Doctor cured the computer, one of the Sevateem, Leela, joined him on his travels. (TV: The Face of Evil)

Their first trip together brought them to a sandminer in the 23rd century. There, the Doctor and Leela were accused of killing members of the crew, and taken prisoner. They later discover 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 brought the intelligent but uneducated Leela to many locations in human history, teaching her about science and her own species' past. In Victorian London, 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)

Another trip to the 20th century brought the Doctor and Leela to a lighthouse on Fang Rock. There, the Doctor discovered a Rutan 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 alien by blowing up the lighthouse. He then found Leela's eye colour had changed as a result of not heeding his warning about watching the explosion. (TV: Horror of Fang Rock)

K9 joins the team
After the secondary control room was destroyed, (AUDIO: Empathy Games) the Doctor and Leela moved back to the original, remodelled control room. 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 young. 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' dog K9 to fight the Swarm-infected humans. Unable to return to Earth with K9, Marius gave the Doctor K9 as a gift. The Doctor bonded fast with the intellgent robot. (TV: The Invisible Enemy)

The Doctor later 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 Fendahl Golden Core, responsible for creating humanity's darker side. Believing it could give them the power to rule the world, a cult used a scientist as a medium for "Eustace". The cult's plan backfired; the core simply began transforming them into Fendahl. A cultist commited suicide, preventing them from reaching the quota of 13 Fendahl. The Doctor blew up their base, killing the transformed humans. He later tossed the troublesome skull into a star to be rid of it and the evil posed by the Fendahl once and for all. (TV: Image of the Fendahl)

Arriving at Megropolis One, Pluto, in the far future, the Doctor stopped a man from committing suicide. 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, and set up a better economy, trapping him in a jar; the true form of a Ursuian was "sea weed". (TV: The Sun Makers)

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 robots. (TV: Underworld)

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 and his companions befriended Ben. Together with the citizens of Prague, they staged a rebellion against the dogs and rebuilt Prague to it's former glory. (PROSE: The Dogs of War)

Noticing the unreliability of K9, the Doctor and Leela aquired the parts for K9 Mark II. (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 as part of a scheme to save his home world from an invasion force of two separate enemies, the Vardans and the Sontarans. He repelled the first group after successfully tricking them, and killed the advance party of Sontarans through traps he set for them when they infiltrated his TARDIS. When all was done, the Doctor seemed not to have any memory of this after being thrown by an explosion.

Upon deciding to leave once more to resume his travelling life, the Doctor found Leela had fallen in love with a Gallifreyan guard named Andred and wished to remain with him; K9 likewise wished to stay with Leela. Though he seemed sad at first to have no companions, the Doctor quickly pulled out a crate marked "K9 Mark II" from a storage area, meaning he would continue spending adventures with his beloved dog. (TV: The Invasion of Time)

Travels with Oliver
Whilst performing repair work on K9, 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 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 Valentine. 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 once again. (PROSE: Puppeteer)

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)

In Scotland, the Doctor attempted to stop the testing of a sonic weapon on a satellite above Earth. But when his efforts failed, sound waves from the satellite resulted in animals and birds becoming wild beasts, which caused them to attack the whole world. Assisted by Colonel Higgs, who thought he was an alien spy, the Doctor launched an American missile at the satellite, which destroyed it and ending the animal aggravated sound. (COMIC: The Unheard Voice)

Returning to Shoreditch in 1963 to deal with an alien insect he left behind in his first incarnation, the Doctor found his past coming back to haunt him in the form of a teenager called Debbie, a schoolfriend of his grandaughter, Susan, who had been investigating the dissapearance of her, Ian Chesterton and Barbara Wright. (PROSE: Those Left Behind)

Hunt for the Hornets
While travelling on his own, the Doctor took up sojourn in a cottage in Sussex called Nest Cottage in the 21st century.

He investigated 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 the Doctor, since he had deemed him a threat. The Doctor discovered the stuffed animals and Percu 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 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 had found out that 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, due to his belief that the circus was evil and corrupted the people of the village. He met Dr Adam Farrow, whose sister Francesca had run away with the Circus of Delights to become "the Bearded Lady of the High Wire." 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 the dwarf, the Doctor found out that Antonio 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. Since then he had set up the circus to draw in more victims for the Hornets, and had remained their central hive ever since. However, after the Doctor had extracted all the information he wanted from Antonio, the Hornets had completely left his body, leaving him a husk, 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, presumably at the Hornets command. 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. Here, the Hornets 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. The Hornets took the possession of wild dogs in order to recapture their queen. 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 Doctor understood how the Hornets were able to take control of Antonio, Francesca, Ernestina, Mrs Wibbsey and Percy Noggins, who were all teetotalers. Also, the Hornets informed the Doctor that they came to Earth by travelling through the dark vacuum of space, explaining how the Hornets in Nest Cottage were nocturnal, having an affinity with the darkness. 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 these Hornets. During this time with Mike Yates, he mentioned his "recent escapades", including "giant rats", "killer robots" and "skulls from the dawn of time". 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's 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. However, using the dimensional stabiliser to shrink themselves would result in the force shield around Nest Cottage being deactivated, allowing the Hornets to be released. 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, in the brain, resulting in a confrontation with the Hornet Queen. It was during this confrontation that the Hornet Queen revealed she had taken possession of Mike, feeding off the negative emotions he felt in his life as a result of his breakdown and his betrayal of UNIT during the Golden Age incident as a means of taking control of his mind. 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 as a result of his time with UNIT. Since the Hornets were no longer restrained by the force shield, they all took their opportunity to return to the hive of the Hornets, 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)

Traps for the Doctor
One year following the battle with the Hornets, the Doctor returned to Nest Cottage to celebrate Christmas with Mrs Wibbsey, Mike Yates and Captain (whom the Doctor gave to Mike to look after once the Hornets had been defeated). 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 an other 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 he 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 near by hotel owned by Frau Herz until the morning. Albert had discovered the Doctor's copy of Albert's 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 now revealed that the hotel was really the dematerialisation chamber, and was in disguise for 40 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 Buddy, Alice's boyfriend. As soon as the Doctor arrived, he felt weak and drained of energy. Mrs Wibbsey and Buddy had taken a now unconcious 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 used dead body drained of energy, similar to the dead bodies from 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 Mrs Wibbsey, or rather, the Hornets that had regenerated inside of her, 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. Therefore, 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 sacrophagus' functions to transport anyone in it, to anywhere in the Atlas. Therefore, using what little remained of the Atlas, the Doctor transported the sacrophagus 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)

Quest for the Key to Time
After activating 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; non-existence would be the price of not cooperating. For his quest, the Doctor was given a new companion by the guardian, Romana. Despite not being too fond of each other, they managed to find the first piece to the Key, which was disguised as a piece of Jethrik two con artist were using in their schemes. Unlike Romana, the Doctor was able to deduce it was the piece they were looking for because the scan showed it moved before being found in a display case; the other valuables were not likely to have been moved. (TV: The Ribos Operation)

While the Doctor and Romana searched for the Key, they were twice interrupted by outside sources emitting chronometric radiation that disrupted the tracer's ability to work, in the form of a chronometric pulse caused by a breach in the higher dimensions (PROSE: Tomb of Valdemar) and a network of spatial teleportation paths created by a malfunctioning time cabinet intersecting with Earth's ley lines. (PROSE: The Shadow of Weng-Chiang) After these two encounters, the Doctor and Romana took a long break from searching for the Key. (PROSE: Heart of TARDIS)

During this break, 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!)

Later, the Time Lords contacted him, telling him that they needed him to go on a mission. The Doctor, however, left them after relearning that the Brigadier was in danger, after he was captured by a terrorist group. The Doctor discovered an Avatar universe that had the Second Doctor, Jamie McCrimmon, and Victoria Waterfield trapped inside. Afterwards, they were forced to continue with the quest. (PROSE: Heart of TARDIS)

They next tried finding a piece to the Key, but ended up caught in the middle of a revolution between the pirates, who were led by the Captain, and the psychically gifted, who grew in number each time their planet materialised over another for riches and resources. Defeating the Captain and his nurse, the real master mind, the Doctor revealed to Romana that one of the planets that was being held as a miniaturised trophy was the second piece. (TV: The Pirate Planet)

He next journeyed to Boscombe Moor, where he found the third piece as the necklace belonging to the intergalactic criminal Cessair of Diplos, who had been posing as an ordinary Earth woman for centuries. Entering a ship stuck in hyperspace above Stonehenge, the Doctor found her thick-headed jailers and tricked them into identifying her (as they did not know what she looked like now). The Doctor then sent them through hyperspace to their intended destination.(TV: The Stones of Blood)

When looking for the fourth piece, 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; Romana was identical to a princess who was being held captive by the vile Count Grendel for his plans to claim the throne before his cousin. The Doctor exposed his plans and went on his way with Romana to continue the search. (TV: The Androids of Tara)

The search for the fifth piece brought the Doctor and Romana to Delta III where the Swampies worshipped an overgrown squid called Kroll, who was attacking a human mining base; it did not differentiatate between them, killing whoever got near. Putting himself in harm's way, the Doctor found Kroll had swallowed the piece to the Key and was transformed by its properties. Reclaiming the piece, he and Romana returned to search for the last one. (TV: The Power of Kroll)

Searching for the final piece brought the Doctor and Romana to a war-torn planet being attacked by a computer-planet near by. There, they met the Shadow, agent of the Black Guardian. Unfortunately, the final piece was in the form of a living being - Princess Astra. Regrettably, the Doctor completed the Key and quickly separated it back into it original components to prevent the Black Guardian from getting it. To prevent the entity from finding him to enact revenge, the Doctor used the Key to install a randomiser in the TARDIS controls; he thought that since he wouldn't know where he was going, there was a good chance the Black Guardian wouldn't either. (TV: The Armageddon Factor)

Destination unknown
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, with the help of human slaves, excavating the remains of the Kaled base for the restored Davros. The Doctor also faced an android race known as the Movellans at war with the Daleks; they both needed someone to reprogram their 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 them on a relaxing holiday to Paris; however, it had "bad taste" in what year to land (1979). There, 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; Scaroth (who posed as Count Scarlioni) was shot by one of his servants due to not wearing his mask to appear human.

The Doctor discovered another version of Scaroth had commissoned Leonardo da Vinci to paint six of Mona Lisa's to give plans for time travel to himself furthest in time. To ensure that future x-rays would know the truth, the Doctor wrote "THIS IS A FAKE" on all the canvasses. (TV: City of Death)

After defeating Scaroth, the Doctor and Romana, due to the faulty randomiser, found themselves in Paris once again - in 2000, and they defeated a minotaur who had kidnapped humans throughout history. (COMIC: The Forgotten)

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)

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 sentience. (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 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 onboard. The Doctor later discovered he had been lied to and the supposed addictive drug vraxoin was actually a valuable material that the Mandrels decomposed into. The Doctor thwarted the 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 dougnuts in the TARDIS food machine, the Doctor set course for the Vita Novus Health Spar and defeated Karna, the director of a company dedicated to creating "the Beautiful People", which consisted of perfect, slim and beautiful human beings. But Karna had been sucking everything out of the human body until there was nothing left. (AUDIO: The Beautiful People)

After saving eleven planets and two space stations, the Doctor took up a hobby: 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)

Continuing to travel with Romana and K9, the Doctor discovered alien children from Eden Twelve had been bringing toys to life on Earth. (PROSE: Child's Play), attended the Queen's re-coronation. (PROSE: The Dying Days), visited a conference on Mars, (PROSE: Beige Planet Mars) visited Cambridge and defeated a mind-draining sphere, (PROSE: Glass) and travelled across the universe to obtain the Great Crystal Choir of Pseudolonica VII. (PROSE: Present Tense)

The Doctor next 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)

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

While the Doctor and Romana were riding a punt on Earth, the Doctor's first four incarnations, along with their companions, were taken by a time scoop to the Death Zone on Gallifrey. The Doctor and Romana were caught in a time eddy and failed to arrive in the Death Zone. They were released once Borusa was sealed in the Tomb of Rassilon. (TV: The Five Doctors)

No more running
The Doctor took a break in Brighton Beach, but landed in the wrong season to do so; K9 also ended up damaged badly when he accidently went into the water. At Romana's urging for a technologically advanced place of relaxation, the Doctor took them to the Leisure Hive, where the remaining Argolins ran it. 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 had to remove the randomiser in order to repair the machine, deciding that he had enough of running from his enemies. (TV: The Leisure Hive)

Repairing K9, the Doctor found himself stuck in a time loop in the TARDIS; he broke it by reenacting the events he was reliving before the loop started over. 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; he shapeshifted by attaching himself to a host. 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)

Travels in E-Space
Despite Romana's protests about being returned to Gallifrey (as she was only meant to be with him to search for the Key to Time), the Doctor was more than willing to comply with the Time Lords' order, hoping to reunite with his old companion, Leela, as well. However, while on course, the Doctor became shocked to discover the TARDIS had fallen through a phenomenon called a Charged Vacuum Emboitment (or "CVE" for short) and into a smaller pocket universe known as E-Space; coordinates for places the TARDIS would land in N-Space would be completely different here. (TV: Full Circle - Warriors' Gate)

Landing on a planet with Gallifrey's coordinates in this new universe, 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 they evolved from each other; 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 (which was the real reason they couldn't leave). During this time he met an Alzarian boy named Adric, whom he found to be nearly as intelligent as himself. Little did the Doctor know, Adric admired him to the point of sneaking on board the TARDIS before they left to find a way back home to their universe. (TV: Full Circle)

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; this gave the Doctor hope of finding a way back home. 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 they MUST destroy. 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; the Three Who Rule aged to dust without the one who turned them alive. Discovering Adric's presence during this adventure, the Doctor vowed to take the brilliant young man back home. (TV: State of Decay)

Around the same time,the Doctor suffered an attack by vampire bats and lost enough blood to put his life in danger. The Eighth Doctor was travelling through his past to regain his memories. He received a blood transfusion from his future self, saving him and ensuring that the Eighth Doctor received all his memories from this life at the same time, letting him move on to the last three. (PROSE: The Eight Doctors)

While travelling through E-space to take Adric home, the Doctor ended up at the Gateway, a location directly between his universe and E-space; time winds blew into the TARDIS and damaged K9 while he was attempting to land. While there, he found Tharils being mistreated by a man named Rorvik in his desperate desire to leave this 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 (the time wind damage prevented him from going back to N-space). As Adric never had any intention of returning home to Alzarius, the Doctor, always needing a companion, allowed him to stay and return to N-Space with him. (TV: Warriors' Gate)

New beginnings
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 found allies in Nyssa and her father, Tremas, when he and Adric were accused of wishing to take the Source for themselves. The Doctor eventualy discovered the Master 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; a new Keeper obtained the Source's power. However, the Master survived and retained enough of the Source's power to merge with Tremas. (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 for Sarah Jane in 1978 at the only address he had for her: the home she had shared with her aunt, Dr Lavinia Smith, on Hill View Road in South Croydon. (TV: The Hand of Fear, A Girl's Best Friend)

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 accidently boarded, thinking the TARDIS was a police box. He also reunited with Nyssa, meeting a being known as the Watcher; they had a secret conversation. Getting the formula, the Doctor shrunk the TARDIS by accident due to the Master's interference; this was corrected. When the Master accidently closed the CVEs by preventing the Logopolians from working, entropy spread; the universe was past its expiration date, so the entropy was sent to other universes through them. As Logopolis vanished, the Doctor obtained the formula needed to permanently reopen CVEs. The Doctor then went to the Pharos radio telescope to broadcast the signal as the Watcher took Adric and Nyssa outside the universe; entropy claimed the Traken Union. (TV: Logopolis)

Regeneration
After successfully reopening the CVEs, the Doctor soon found himself trying to stop the Master from forcing the universe into serving him 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 his old foe rotated the dish. The Doctor then experienced visions of his past companions - the Brigadier, Benton, Sarah, Harry, Leela, K-9 and Romana. He then saw visions of some of his past foes, such as Davros and the Black Guardian; all of those he saw called to him. Losing his grip, the Doctor fell to the ground. When his companions gathered around him, the Doctor told them that it was the end (of this incarnation), but the moment (of his regeneration) had been prepared for. Shocking everyone present, the Doctor held his hand out to the Watcher, who had just appeared, and merged with him. Nyssa then exclaimed in surprise that the Watcher had been the Doctor all the time; he then regenerated into his next incarnation. (TV: Logopolis)

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 attended the funeral of Alistair Gordon Lethbridge-Stewart. (PROSE: The Gift)
 * River Song met the Fourth Doctor, writing in her diary that he had a whole room just for his scarves. She wiped his memory with mnemosine recall-wipe vapour so their personal timelines wouldn't be contaminated. (GAME: The Eternity Clock)

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: "I shall still think of myself as 743 ... or was it 730, I never can remember..." (DWM: The Time Witch)
 * See separate article.

Personality
The Doctor's fourth incarnation was definitely the least human-like in nature, and he stood apart from others, even most of his own people. (TV: The Deadly Assassin, The Invasion of Time)

The Doctor was known to be aggressive as when the Krynoid pods came to Earth (TV: The Seeds of Doom)

When Sarah upbraided him over his callousness at the sight of Laurence Scarman killed by the animated corpse of his own brother, the Doctor reminded her of the larger issue of stopping Sutekh. (TV: Pyramids of Mars) His mind often leapt ahead of anyone, including himself. He delighted in keeping both friends and foes alike off guard with oddball humour and curious pranks, as in his second incarnation. Although generally peace-loving and kind-hearted, as were most of his incarnations, the Doctor could also react with sudden violence when necessary. He was also not against taking a life in extreme circumstances, (TV: The Brain of Morbius, The Ribos Operation) but would scold Leela multiple times for unnecessary killing. (TV: The Face of Evil)

He told the mutating Sorenson that the results of his experiments were his own fault, but did however rescue Sorenson when the process was reversed. (TV: Planet of Evil)

He could judge character keenly, almost instantly knowing whom to trust or seeing through Unstoffe's false guilelessness. (TV: The Ribos Operation) Of all of the Doctor's incarnations, this one had perhaps the most consistently anti-authoritarian attitude, with little tolerance for religious dogma. (TV: The Brain of Morbius, Underworld, The Stones of Blood, The Power of Kroll) or nationalism. (TV: Robot, The Armageddon Factor) The Doctor often played the fool to lull his opponents, such as Count Scarlioni, into underestimating him, though it did not work in Count Scarlioni's specific case. (TV: City of Death)

Despite his charm and offbeat humour, the fourth incarnation was arguably more aloof and sombre than his previous incarnations. He could be intensely brooding, serious and even callous, and would keenly scrutinise his surroundings even when playing the fool. He would be furious with those he saw as stupid, frivolous, misguided or evil. When taking charge, he could be considered authoritative to the point of egocentricity, but he was usually the only one capable of solving the situations he found himself in. He generally maintained his distance from the Time Lords, even after they had lifted his exile, and resented that they were capable of re-entering his life when they deemed it necessary. Not only did he seem more inclined toward a solitary existence, (TV: The Deadly Assassin) he also emphasised his distance from humanity, although he stated on more than one occasion that he found mankind to be his favourite species. (TV: The Ark in Space)

Unlike his third incarnation, this incarnation did not maintain a close working relationship with UNIT or the Brigadier, a trend which carried forward with his future incarnations. The Fourth Doctor reacted with anger when UNIT recalled him to Earth. (TV: Terror of the Zygons) Except for this and a handful of other occasions, the Doctor kept his distance from UNIT.

As the youngest-appearing incarnation at the time, the Doctor found himself drawing closer to some of his companions than he might have previously, in particular, with Sarah Jane Smith. (TV: School Reunion) If any of his other female companions felt the same way, the Doctor, through intent or quirk of personality, did not appear to notice. He tended not to display such feelings himself, not even when accompanied by the often scantily clad Leela, although during one adventure he acknowledged the fact that Romana was attractive, (TV: The Pirate Planet) and in another adventure he even kissed her. (PROSE: The Well-Mannered War) He was more likely to make remarks such as telling Countess Scarlioni, "You're a beautiful woman ... probably". (TV: City of Death)

Habits and Quirks
Souvenirs from many different worlds littered the fourth incarnation's pockets. (TV: Robot, Genesis of the Daleks) He would sometimes relax by playing with a yo-yo and liked to drink ginger beer. (TV: The Android Invasion)

He would often have jelly babies with him and offer them as a greeting. While past and future incarnations also showed occasional fondness for the sweet, it was never as frequent as this incarnation's love for them. In his later life he developed a great fondness for tinkering about in his TARDIS. He relied upon his sonic screwdriver at least as much as in his previous incarnation.

He was also not adverse to winding up his companions on occasion, such as once fooling Leela into standing and playing with a yo-yo for an extended period of time, with her believing it was an experiment. (TV: The Robots of Death) On another occasion, he caused Romana to nearly panic when he pretended to become possessed by the Black Guardian. (TV: The Armageddon Factor)

Skills and abilities
The Doctor possessed telepathic powers, allowing him to communicate with other telepathic users. While later incarnations such as the Tenth and Eleventh Doctors had to make physical contact to use telepathy, this 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. It was unclear if he was using telekinetic powers himself combined with that of the Mentaids or if he was simply guiding them. (TV: The Pirate Planet)

The Doctor was also shown to be a highly skilled swordsman, being able to hold his own against Count Grendel, who was considered to be the finest swordsman on Tara. He disarmed Grendel but allowed him to pick up his sword. Although the Doctor was unable to defeat Grendel or disarm him a second time, he did ultimately force the Count to retreat. He later joked about Grendel's sword skills, asking, "Was he supposed to be good?" (TV: The Androids of Tara)

The Doctor also claimed to be a master hypnotist and used a watch to hypnotise people or break other hypnotists' hold on them. (TV: The Talons of Weng-Chiang)

Appearance
In stark contrast to the elegant and refined, but somewhat flamboyant, figure of his third incarnation, the fourth incarnation was an unkempt, awkward-looking figure, dressed in battered clothing and a ridiculously long, multi-coloured scarf, 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 large floppy hat. Professor Marius remarked that the Doctor looked like a "space vagrant". (TV: The Invisible Enemy) The fourth incarnation was also notable for being the first incarnation to wear clothing with question mark motifs, later worn by his fifth, sixth and seventh incarnations. (TV: The Leisure Hive, Castrovalva, The Twin Dilemma, Time and the Rani, et al.)

His costume changed throughout his life. His initial costume consisted of a red-brown blazer with elbow patches, baggy grey tweed trousers, a dark brown cardigan with diamond shapes adorning the front, a white dress shirt and a long green neck-tie. (TV: Robot - Revenge of the Cybermen) It changed slightly with a different scarf and hat (TV: Terror of the Zygons) and again with the original scarf, albeit a different waistcoat, shirt and cravat. (TV: Planet of Evil) Eventually, the basic style stabilised with a frock coat and some form of a cravat or tie with the above mentioned articles of clothing. (TV: The Android Invasion) He wore several frock coats of different colours, including a dark brown one, (TV: Pyramids of Mars) a light grey one, (TV: The Brain of Morbius) and a light brown one.

Throughout his life, his costume alternated with different shirts, cravats, frock coats, waistcoats and other various pieces of clothing until he later settled on one outfit consisting of an open-neck shirt, an unbuttoned waistcoat, a tan frock coat, knee-high leather boots, trousers and his scarf. (TV: The Power of Kroll) He wore this costume alternating between ankle-high leather shoes and the boots. (TV: City of Death, et al.) From his second attempt to reach Brighton Pavilion, however, his costume changed dramatically, with a red and maroon colour scheme. This consisted of a full-length maroon coat, waistcoat, trousers, buccaneer-style leather boots, a Poet's Hat, a white open-neck dress shirt with question marks adorning the collars (a trait that continued through to his fifth, sixth and seventh incarnations) and a new scarf. (TV: The Leisure Hive) This scarf was longer than his previous scarves; when it was looped around his neck, the loop reached the floor, and so did the ends. He adopted a maroon, red and purple colour scheme to match the rest of his clothes. He continued to wear this until the end of his life. (TV: Logopolis) His costume regenerated slightly when he did, as seen by the Fifth Doctor's ankle-high golf shoes and pulled-up socks instead of the leather boots. (TV: Castrovalva) The Doctor had kept parts of his costume throughout the years. (TV: Time and the Rani, The Christmas Invasion)

Like several of his later incarnations, his pockets were dimensionally transcendental. The array of items he carried included:
 * a seemingly endless supply of Jelly babies
 * a galactic passport (TV: Robot)
 * a cricket ball (TV: The Ark in Space, The Hand of Fear)
 * a yo-yo, which, with a sheepish grin, he would explain was useful for taking gravity readings (TV: The Ark in Space)
 * a selection of books, including his 500 Year Diary, (TV: The Sontaran Experiment) Oolon Caluphid's Origins of the Universe and a Tibetan language handbook (TV: The Creature from the Pit)
 * a magnifying glass, gemstones, handcuffs, and an etheric beam locator which also detected ion-charged emissions (TV: Genesis of the Daleks)
 * a lockpick (TV: Pyramids of Mars)
 * a football rattle
 * a magician's cane (TV: The Hand of Fear)
 * a clockwork egg-timer (TV: The Face of Evil)
 * a breathing tube, a barrister's wig, 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)

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 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's hyperspace.

Tom Baker, as the narrator of the series, has referenced Doctor Who. He also appeared in Doctor Who and the Daleks in The 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.

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.

Reprising the role
Unlike his predecessor Jon Pertwee and 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, TV: 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 HOMEVID: 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 NOTDWU: 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.

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 AUDIO: 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 3rd 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. .

The Brilliant Book 2011
According to The Brilliant Book 2011, a non-narrative source, the Fourth Doctor, posing as a Punch and Judy man, met Winston Churchill in 1879 whilst hunting Cybermats.