The Other

The Other was one of the original founders of Time Lord society, along with Rassilon and Omega. The origin of the Other remained a mystery for later Time Lords.

The Other had a mysterious connection to the Time Lord known as the Doctor. According to some accounts, the Other was reincarnated via the Loom of the House of Lungbarrow to become the Doctor. (PROSE: Lungbarrow) The Eleventh Doctor briefly used "the Other" as an alias when confronting a younger Rassilon on ancient Gallifrey, having travelled back in time to aid in the start of Time Lord civilisation. (COMIC: The Lost Dimension) There were even accounts suggesting that the First Doctor was simply an aged version of the Other, and left Gallifrey fully cognizant of his enormous age and part in the founding of Time Lord society, though Gallifreyan society had forgotten him over the centuries as he faded into obscurity. (PROSE: Remembrance of the Daleks, Human Nature)

Ancient being
While inside the Doctor's mind, Emily Hutchings experienced a flash of memories from something ancient and powerful which had died during a war in the Dark Times. While being "too much to die fully", it was also "too much to remember", with the only clear memory being its cry of defiance as red blood burst from it as it was destroyed. The Other lived on in an unknown state for a very long time afterwards, witnessing the rise and fall of many planetary civilizations, until it lost its memories the moment it was born from the womb of the Doctor's mother and became the First Doctor. (PROSE:  Revelation)

The Vampire Wars were a notable Dark Times conflict, during which powerful beings such as the Great Vampire were killed. Riddles and marginalia in the ROO texts, which contained information on the Other, indicated that during Rassilon's recorded meeting with the Great Vampire something was secretly stolen from the Great Vampire. Ruath believed that Rassilon stole genetic material which was used to give the Gallifreyans regeneration, explaining why Time Lords shared 98% of the same genes as Vampires, but the Doctor believed that this was a half-truth. (PROSE: Goth Opera)

The Other once mentioned to Rassilon that their relationship, through which the Other gave Rassilon the power to create Time Lord civilization, was not a strict blood-bargain or pact but instead something on the approval of the being which had sent the Other to Rassilon.

Civilizations other than the Time Lords had origin myths with figures recognizable as forms of the Other, as seen with the Tharils. Furthermore, the Tharil account of the Black and White Guardians forming the universe portrayed the Red Guardian as Otherly, raising the possibility that the Time Lord Other was a manifestation of that same cosmic being. (PROSE: Lungbarrow)

The son of Leela and Andred
When the Seventh Doctor, nearing the end of his life, learned that Leela was pregnant with Andred's child, he looked into her eyes for a long moment, "as if recognising something there". He remarked, "A father from Gallifrey and a mother of Earth stock. That's an unusual pedigree." When Leela apologised for not bringing a parting gift, the Doctor said, "Just call him after me." Leela looked startled, then nodded. (PROSE: Lungbarrow) Soon after his regeneration, the Eighth Doctor told Grace Holloway, "I'm half human, on my mother's side." (TV: Doctor Who)

"The Old Man and the Police Box"
After the Doctor turned himself into a human, John Smith, strange repressed memories surfaced, inspiring him to write a children's story, The Old Man and the Police Box. It followed the adventure of a silver-haired inventor from England during the reign of Queen Victoria. The Old Man invented the first police box, initially to help police, but then upgraded it to become dimensionally transcendental and able to travel through time and space.

Being lonely, the Old Man set off in his police box to explore the universe. He discovered a jungle planet called Gallifrey, and taught the natives science and technology, elevating them to a mighty civilisation rooted in British ideals of law and peace. When the Gallifreyans became boring, the Old Man invented a way for them to begin life anew, and implanted them with a second heart in the hope that it "would make them happier"; however, these measures only served to make them live longer, not more interestingly.

Eventually, the Old Man grew so bored that he stole a time machine and returned to Earth, breaking one of the very laws he had created. He knew the Gallifreyans would pursue him, but he had decided that "being free was better than being in charge." (PROSE: Human Nature)

A stranger from the future
One account stated that a Time Lord calling himself the Stranger originated from a time long after Rassilon's life. Though Rassilon feared that the Stranger was planning to erase his people from history in revenge for being shunned, the Stranger was intent on guiding Time Lord civilisation away from tyranny. He travelled back in time to seven days after Rassilon had returned from the Eternal War and took power. With a pass signed by Rassilon himself, the Stranger gained access to the restricted areas of the Citadel and for the next few months offered advice to Rassilon without providing any detailed information. (PROSE: The Scrolls of Rassilon)

The Eleventh Doctor briefly referred to himself as "the Other" during his intervention into the creation of the Type 1 TARDIS. Rassilon noted that he was acting just like the "chrono-scrollwriters of old" by refusing to give his real name. During his prolonged, time lock-defying stay on Ancient Gallifrey, the Eleventh Doctor also advised Rassilon in technological matters, with Rassilon admiring the man's unorthodox genius but remaining wary of him, noticing a familiarity within the Doctor. (COMIC: The Lost Dimension)

Gallifreyan
According to some accounts, all three members of the Triumvirate were Gallifreyans, and in life they were of equal standing; it was an accident of history that Rassilon and Omega became legends and household names while the role played by "the other" was forgotten over the millennia, his very name becoming obscure. (PROSE: Remembrance of the Daleks) In some of the instances in which he hinted as to his past as a contemporary of Rassilon and Omega, the Doctor seemed to be fully aware of his past reaching back before the First Doctor, (TV: Remembrance of the Daleks) with the Second Doctor being aware of having regenerated in the past. (PROSE: The Power of the Daleks)

Shaping the history of Gallifrey
At some point, the Other encountered Rassilon, whom he offered various powers. The Other would later deny that their collaboration had been "a blood-bargain or a pact", as "I was merely sent on approval"; Rassilon replied, "On my approval, or yours?" (PROSE: Lungbarrow)

Time travel, the living Chapterhouses, the Looms, and peace on Gallifrey were all made possible by the Other. Millennia later, the House of Lungbarrow still remembered him from the time before it was a seedling, when it was "just an insubstantial idea" in the Other's mind. While Loom-born Time Lords had thirteen lives each, the Other at one point seemed incapable of regeneration, and told Rassilon that they were both "doomed relics of another age", with "one brief life apiece." (PROSE: Lungbarrow)

A "stranger in the shadows" chastised Rassilon when he taunted the Pythia. (PROSE: Cat's Cradle: Time's Crucible)

The Other was the founder of the Interventionists. Millennia later, Cavis mused that travel, extreme violence, and "Murder, sex and adventure in exotic frocks" were the zenith of what the Other had envisioned. (PROSE: The Shadows of Avalon)

Soon after the Pythia's curse and death of Rassilon's unborn child, the Other presented Rassilon with a gift, an onion, upon peeling away the layers of the onion Rassilon witnessed how the onion continued to get larger, the more layers were peeled away; thus the Other introduced Rassilon to the concept of Dimensional Transcendentalism. (PROSE: Cat's Cradle: Time's Crucible)

According to The Thousand and Second Night, someone who was neither an "angel" nor a "djinn" advised "Allah" to hide the caldera inside Earth. The Shift later claimed to have been this person. (PROSE: Head of State, Interference)

The Other was influential during the Dark Times on Gallifrey after the cult of Pythia had ended. He enjoyed spending time in a garden of pearl-grey roses atop the Omega Memorial, the tallest tower in the Citadel, and sometimes played chess with Rassilon there. The Other shared some sort of bond with the Hand of Omega, which began to follow him after the death of its creator. (PROSE: Lungbarrow)

When Omega's plans to detonate the Q star were close to fruition, the Stranger explained his origins to Rassilon. The Stranger pleaded with Rassilon to make the Time Lords less powerful and less stuck in their ways, believing that in doing so the Time Lords of the future he came from would be open to new ideas. Rassilon refused to abandon his philosophies, intending for Gallifrey to become the powerful society that he had always planned.

The Stranger visited Rassilon's quarters angry about the release of the virus that gave the Gallifreyans the ability to regenerate, as it wiped out a large proportion of the population upon its release.

Shortly before the detonation of the Q star, the Stranger materialised his TT capsule on Rassilon's ship, and once again pleaded with him to alter the course of established history. Finally understanding that Rassilon would not change his mind, the Stranger left in his ship. However, respecting the Stranger's audacity, Rassilon decided to ensure Gallifreyan society would never tolerate tyranny. It also led him to write the first Law of Time. (PROSE: The Scrolls of Rassilon)

According to an account, years after Omega's death, the Other watched from the Omega Memorial as Rassilon's rule moved closer to despotism and Gallifrey's borders were sealed. Sickened and weary of the violence, and blaming himself for what was happening to Gallifrey, he intended to put an end to these games and fling himself back into the Universe, as a piece on the board rather than as a player. Knowing that Rassilon would try to use his family as a hostage to force him to remain, he bid goodbye to his granddaughter Susan, telling her to go to safety on the planet Tersurus. He then hurled himself into the Prime Distributor of the Looms, his entire DNA and Genetic Code being torn apart and unravelled to await his eventual reconstitution millions of years later. (PROSE: Lungbarrow)

Re-Loomed
After the Other threw himself into the Prime Distributor, he was re-Loomed some ten million years later to the House of Lungbarrow as the Time Lord who became known as the Doctor. (PROSE: Lungbarrow) That entire generation was affected by anomalies in the Looms, resulting in several other renegades. (PROSE: The Book of the War)

While at the Time Lord Academy, the First Doctor had certain "other studies" which involved him being an acolyte to the hermit. In one ritual which he would not grasp or understand until centuries later, the Doctor made supplication to taboo powers and spoke a rhyme learned from the heart of his own being to a sarlain. This ritual was of immense significance, to the point of it seemingly forcing the Doctor and Susan to flee Gallifrey, and the hermit later referred to the Doctor as "my child, my elder, and my contemporary", indicating that it may have somehow retroactively bound the Doctor with the Other. (PROSE:  Revelation)

Before initially fleeing Gallifrey for the first time, the First Doctor was rescued by the Hand of Omega, which had sensed him as the reincarnated Other. The Doctor, along with the Hand of Omega, boarded a stolen Type 40 TARDIS, which the Hand of Omega hacked, allowing for the Doctor to be transported millions of years into Gallifrey's past, something that Time Lord law forbade. While on Ancient Gallifrey the First Doctor encountered Susan, who recognised him as her Grandfather. While initially hesitant, the Doctor came to accept that he was Susan's grandfather. The Doctor rescued Susan from away from ancient Gallifrey, (PROSE: Lungbarrow) possibly briefly settling on modern Gallifrey before being apprehended by the President's Guards. (PROSE: The Longest Story in the World)

It was a chance encounter with the Book of the Old Time that first pushed the Doctor's mind back to his role in his people's ancient past, leading him to think that before Regeneration there had been Reincarnation. (PROSE: Cat's Cradle: Time's Crucible) While in the Tomb of Rassilon with three of his future selves, the First Doctor instantly recognised "the voice of Rassilon". (TV: The Five Doctors)

During regenerations, the Doctor was able to gain skills from the Other. The Third Doctor once theorised that his incarnation's newfound skill in martial arts was his body remembering abilities from a previous life. (PROSE: Country of the Blind) The Other had regularly communicated with a Tersuron servant, (PROSE: Lungbarrow) and an alternate Ninth Doctor was later able to speak perfect Tersuran. (TV: The Curse of Fatal Death)

By the Doctor's seventh incarnation, he had apparently realised his earlier identity. Lady Peinforte threatened to reveal it, (TV: Silver Nemesis) and Cavis and Gandar hinted at it in their conversations. (PROSE: The Shadows of Avalon)

When the Seventh Doctor transformed himself into a human named John Smith, he removed almost all of his memories, but he was unable to remove the ones from before he was born. "Verity" kept these memories out of John Smith's head. (PROSE: Human Nature)

Legacy
The First Doctor was taught in history lessons that Rassilon had banished the Other from Gallifrey, and that the Other had stolen the Hand of Omega when he left, never to return. A conflicting legend held that the Hand had pursued the Other across the stars of its own volition. (PROSE: Lungbarrow)

Scholars later called documents concerning Rassilon, Omega and the Other the ROO texts. (PROSE: Goth Opera)

A minor Gallifreyan festival known as Otherstide was celebrated yearly in his honour. It coincided with the Doctor's naming day/Birthday. (PROSE: Lungbarrow, AUDIO: Cold Fusion)

Gallifreyans in the Doctor's time performed puppet shows commemorating the lives of the founders. The puppet version of the Other was faceless and wore a black cowl. (PROSE: Lungbarrow)

Secret societies on Gallifrey were dedicated to the worship of Rassilon, Omega, and the Other. (AUDIO: Intervention Earth)

In a parallel universe where the Sixth Doctor led Gallifrey in the War, the Master commanded a time dreadnought named the Arcane Mystery of the Other. When he defected to the enemy, the ship was thought lost; in reality, it was being dissected in an enemy shipyard. (PROSE: The Quantum Archangel)

Glospin believed that the Other's coming to House Lungbarrow was the reason the family were "all mad". (PROSE: Lungbarrow)

, while posing as the Doctor, claimed that Rassilon, as well as the "forefather of all Time Lords", had been his mentor. (PROSE: The Novel of the Film)

The Time Lords had several curse words derived from the Other's name. These included the expletives "Othering" and "Otherlingly", which were used to add emphasis (e.g. "Othering nuisance", "Don't be so Otheringly flippant!"). (PROSE: Lungbarrow) The Celestial Intervention agent Gandar, referring to the Eighth Doctor, said "Let's just kill the Otherf–" before being cut off. (PROSE: The Shadows of Avalon)

Behind the scenes

 * The Other's first direct appearance was in Ben Aaronovitch's Target Books Remembrance of the Daleks, in a brief flashback to the time of Rassilon.
 * Daryl Joyce's half-hidden illustration of the Other's face on the cover of the ebook reissue of Lungbarrow appears modeled on British actor . Campbell was the mentor of Sylvester McCoy, and actually auditioned for the part of the Seventh Doctor himself before McCoy was chosen over him, as Campbell's performance in his audition was deemed too eerie.
 * The Cartmel Masterplan allegedly included a revelation that the Other was an incarnation of the Doctor. Following the show's cancellation in 1989, these plans were continued in the New Adventures novel line. (DWM 341) However, the guidelines given to the Virgin writers stated that the Other was not the Doctor. (REF: A History of the Universe) According to Ben Aaronovitch in DWM 147, Platt, Cartmel and himself "all [had] similar, but slightly different, views of who [the Doctor] really is".
 * In the afterword to the digital edition of Lungbarrow, Marc Platt identified Guiseppi Verdi's opera Rigoletto as an influence on his portrayal of the Other's relationship with Susan: "This other grandfather keeps Susan hidden away, just as the Duke of Mantua's hunch-backed jester, who was party to all sorts of his master's debaucheries, hid his own innocent daughter from reality – with particularly blood-curdling results."
 * Platt cast doubt on the Other's planet of origin, saying: "This shady figure, whoever he is, has obviously been on Gallifrey long enough to become a grandparent, although we don't know to which of Susan's parents he is the father. He may not even be Gallifreyan himself. Who knows?"
 * Platt described the Other and his final confrontation with Rassilon in terms of British politics: "He is an eminence grise; the power lurking behind the throne, like a skulking, limelight-shunning version of Alastair Campbell or Peter Mandelson, who manipulates the emergence of Gallifrey as one of the supreme seats of power in the Universe. But Blair and Campbell/Mandelson are puny substitutes for Rassilon and the Other. Only Thatcher (all squawks and eyepatch), from whose evil Pythian empire a new world is being built, is worthy of comparison."
 * Platt intended the Other's rose garden to recall the one in which the First Doctor is seen in both The Three Doctors and The Five Doctors, and said that it reappeared as the Doctor's imaginary rose garden in his Unbound audio Auld Mortality.
 * According to PROSE: The Scrolls of Rassilon, the Stranger had a detailed knowledge of Gallifreyan history and imparted some of that knowledge to Rassilon. The Stranger first became known to Rassilon in the weeks before Omega destroyed the star Qqaba to bring Gallifrey its power over time. The clear implication was that the Stranger was the Doctor, gone back in time in an attempt to make Gallifrey more open-minded.
 * In Lungbarrow, the Other states that he came to Rassilon "on approval". Platt has elaborated that this meant Rassilon had "acquired" the Other "in some sort of pact with God knows what". (DWM 305)
 * Platt confirmed that he intended to imply that Leela and Andred's child would go on to become the Other, explaining the Doctor's half-human heritage in the 1996 TV film. (DWM 305)
 * In 2013, when asked how he would respond if presented with a theory that the Other was Nyarlathotep, Andrew Cartmel said, "I would respond, "Who is Nyarlathotep?" while scratching my head."
 * When asked if Kopyion Liall a Mahajetsu from The Pit was intended to be the Other, author Neil Penswick stated that he was not.
 * John Smith's account of the "Old Man" somewhat resembles the story of Dr. Who from the Dalek movies, the most significant difference being that Dr. Who, despite dressing in approximately Victorian garb, came from the 1960s. In the acknowledgements, Paul Cornell states that this section of Human Nature was plotted by Steven Moffat.
 * In the scene corresponding to the point in The Timeless Children where Tecteun's male incarnation stands alongside two other Time Lords in full high-collared regalia, the Timeless Children script release mentions that "we can assume [the other two] are Rassilon and Omega". This would cast Tecteun as the "mysterious third founder", although according to The Timeless Children it is not Tecteun themself who has a mysterious connection with the Doctor but Tecteun's ward and experimental subject, the Timeless Child.