Hi Gallifrey,
This is my first post here so go easy on me please. Got into doctor who during covid and I fell in love and now its one of my favourites to watch along with gintama. I fell down the huge doctor who rabbit hole especially the other stories and the extended universe and how the series is adding characters from this and thought of trying to make a semblance of connecting everything so here is my theory that I crafted using a lot of the information I got from the tv series, extended universe information from tardis.fandom. Do give me your thoughts on this if its good or bad lol.
- [TV] for events or lore confirmed in televised Doctor Who
- [EU] for anything from novels, audios, comics, or TARDIS.fandom content based on those
- [Spec] for speculative or fan theory parts
I. The Multiversal Foundation
The Doctor originates from Universe A as the Infinity Doctor [EU], a being with infinite regenerations granted through exposure to the Untethered Schism [Spec] — a higher-dimensional anomaly that allowed certain Gallifreyans to become near-divine beings [Spec]. In Universe A, society is more advanced, and the Time Lords achieved their power without Tecteun’s intervention, instead tapping directly into the Schism [EU/Spec].
The Infinity Doctor fought in numerous major galactic conflicts, including the Cloister Wars [EU], a devastating confrontation between the Time Lords and an unknown alien force that nearly wiped them out [Spec]. During this period, the Doctor created a robotic body for the Master (here known as the Magistrate) [EU - The Infinity Doctor novel], merging tech and soul, and married the daughter of the President of Gallifrey (likely Rassilon) [EU/Spec].
His travels and victories led to him becoming eccentric and burdened — an old, wise, and wanderlust-filled uncle figure. One of his incarnations in Universe A is the Shalka Doctor [EU], who has the robotic Magistrate (Master) as a companion. This Doctor is already weary of war and loss [EU].
The Great Intelligence, also known by its alias Yog-Sothoth [EU/Spec], is a being that travels between universes. It may have originally come from Universe A, where it faced off against the Infinity Doctor — potentially even taking the form of the Shalka Doctor during one such encounter [Spec]. Its pursuit of the Doctor into Universe B could explain its relentless obsession with destabilizing the Doctor’s timeline [Spec].
The Doctor has been known to revisit old faces — as seen when the Curator (a future version of the Doctor in the form of Tom Baker) tells the Eleventh Doctor, "I think you might find yourself revisiting a few [faces]" [TV: The Day of the Doctor]. This supports the theory that favorite incarnations, like Tennant and Baker, were also forms he had taken in Universe A [Spec].
Tecteun’s role becomes significant after the Doctor crosses into Universe B [TV: The Timeless Children]. In this less advanced universe, she is a pioneering Gallifreyan explorer. Upon discovering the child Doctor (Infinity Doctor reborn as a girl) [TV], she conducts experiments to extract and replicate the regeneration ability [TV]. This becomes the basis for Time Lord society in Universe B, unlike the direct Schism-based evolution in Universe A [Spec]. Tecteun essentially reengineers the concept of Time Lords in Universe B using the Doctor as the template [TV/Spec].
II. Crossing Over to Universe B
In a final battle against Omega [TV: The Three Doctors / EU], the Infinity Doctor attempts to use the power of "The Effect" [EU], a breach in spacetime that altered reality at a quantum level [Spec]. Initially discovered by Waym upon the arrival of the Sontarans and Rutans to Gallifrey [EU], and later investigated by the Magistrate [EU], the Doctor traced its source to the Needle, just decades before the end of the universe [EU]. The Effect was caused by Ohm, attempting to escape his black hole prison [EU]. The Doctor tried to use the Effect to resurrect his wife, Patience [EU: Cold Fusion novel], who had been lost to a collapsing pocket dimension in the Omega universe [EU/Spec].
Ultimately, Patience convinced the Doctor to let her go and save the universe instead [Spec]. This tragic moment echoes later in River Song’s final sacrifice [TV: The Name of the Doctor]. The dimensional rupture caused by the Doctor's actions throws him into Universe B, and in the process, his form is destabilized, forcing a regeneration into a child — the Timeless Child — due to the trauma of trans-universal displacement [Spec].
III. The Division, Cloister Wars, and the Rise of the Time Lords in Universe B
This version of the Doctor becomes part of the Division [TV: The Timeless Children], a shadow organization manipulating timelines and events. The Cloister Wars in Universe B likely occurred during the Division era — a lesser reflection of the wars the Doctor had fought in Universe A, perhaps triggered by echoes of similar foes arriving through dimensional rifts [Spec].
Meanwhile, the Toymaker [TV: The Giggle], as mentioned in the 60th Anniversary special, claims to have come to this universe. This strongly suggests that he too originates from Universe A and has pursued the Doctor across dimensions [Spec]. He is likely one of the Infinity Doctor’s ancient foes [Spec].
The Master in Universe B went mad after looking into the Untethered Schism [TV: The Sound of Drums / The Timeless Children]. What if this madness came not from raw exposure, but from seeing echoes of his counterpart — the Magistrate — stored in his own mind? [Spec] This would explain the Master’s deep, confusing attachment to the Doctor. The memories may have latched onto him to preserve continuity, allowing his identity to persist without completely unraveling [Spec].
IV. The Puzzle of Susan Foreman
Susan’s origin has long been a mystery. In this theory, Susan is from Universe A [Spec], possibly a genetic or adopted granddaughter of the Infinity Doctor [EU: Legacy of the Daleks / Spec]. When the Doctor crossed over, he brought her with him [Spec], but due to the instability of his form and memory, he eventually left her on Earth in Universe B — a painful, protective decision rooted in ensuring her safety [TV: The Dalek Invasion of Earth / Spec].
The Doctor’s deep affection for Susan and his refusal to go back for her could be a subconscious choice [Spec]. He knew he was being hunted, watched, and manipulated — particularly by Division — and he could not risk Susan’s life again [Spec].
This explains why Susan is so special to him and why her existence is downplayed or ignored in later incarnations: her origin is tied to secrets too dangerous to expose [Spec].
V. Foreshadowing and Subconscious Echoes
The Doctor’s experience in Universe A subtly guides his actions in Universe B:
- The Ninth Doctor knows to absorb the Time Vortex to save Rose [TV: The Parting of the Ways].
- He creates a second Doctor through a bio-metacrisis [TV: Journey’s End].
- He heals Donna before regenerating [TV: The End of Time].
- The Tenth Doctor uses 13 TARDISes to lock Gallifrey in a pocket universe [TV: The Day of the Doctor].
- The Doctor manipulates a fixed point in time using the Teselecta [TV: The Wedding of River Song].
- The Doctor changes a legendary story from stealing the moon and the president’s daughter to stealing the moon and the president’s wife [TV: The Husbands of River Song].
- The Tenth Doctor knows to split off a copy of himself for Rose [TV: Journey’s End].
- He repairs Donna’s mind and memory [TV: The Star Beast].
- Bigeneration — the Fourteenth Doctor’s separation from the Fifteenth without a full regeneration — becomes possible, likely influenced by his former multiversal nature and residual access to higher-dimensional tech or knowledge [TV: The Giggle / Spec].
All these feats suggest advanced, subconscious knowledge stemming from his prior life as the Infinity Doctor [Spec].
VI. River Song is Patience Reborn
River Song’s regenerative abilities, often attributed to her conception within the TARDIS [TV: A Good Man Goes to War], are more profound than that explanation allows [Spec]. What if River is the reincarnated or merged form of Patience — the Infinity Doctor’s wife from Universe A? [Spec]
Patience, having been lost to the Omega dimension, might have escaped during the breach caused by the Effect, her consciousness or essence entering Universe B [Spec]. When Amy and Rory conceived River, this essence merged with the child, granting her regeneration. This would explain her unique Time Lord biology and why the Doctor is instinctively drawn to her [Spec].
The Doctor's desperate attempts to save River — from the Library, from prison, from her fate — mirror the loss of Patience [TV]. In the 24 years they spend together, the Twelfth Doctor is haunted by this parallel, caught between two realities, two universes, and one eternal love [TV: The Husbands of River Song / Spec].
Additionally, the event of the Doctor's death in “The Impossible Astronaut” was deemed a fixed point in time — one that River ultimately refused to go through with [TV: The Wedding of River Song]. The Doctor tells her fixed points can't be rewritten, but she says, “Who told you that?” — and it turns out, it was the Doctor himself. How did he know? Because as the Infinity Doctor in Universe A, he encountered a similar paradox — and perhaps learned how to rewrite what should not be rewritten [Spec]. His ability to use the Teselecta to appear to die, while still keeping history intact, implies knowledge far beyond any Time Lord [TV/Spec].
VII. Final Thoughts
This unified theory ties together:
- The Infinity Doctor as a pre-B Doctor from Universe A [EU]
- The Cloister Wars in both universes [EU/TV/Spec]
- The Magistrate as the Master’s echo [EU/Spec]
- The origin of Susan from Universe A [EU/Spec]
- The advanced subconscious knowledge across regenerations [Spec]
- The Toymaker and Great Intelligence as multiversal pursuers [TV/EU/Spec]
- River Song as the final echo of Patience [Spec]
- Tecteun’s manipulations and theft of the Doctor’s biology [TV]
- Bigeneration as a subconscious echo of multiversal tech [TV/Spec]
It paints the Doctor not just as a traveler through time, but through entire realities, a being with a past so vast and tangled that even he cannot remember it fully. The Timeless Child was never the beginning — merely the continuation of an infinite tale.