Doctor Who's shocking Timeless Child twist actually pays off some major stories from the Tom Baker era. The Doctor Who season 12 finale finally resolved the mystery of the Timeless Child, and it's no exaggeration to say the show will never be the same again. The Doctor is far more than just a Time Lord; she is the Timeless Child, originating from realms unknown, with unlimited regenerations and a history stretching back before the dawning days of Time Lord civilization. This is probably the biggest retcon in Doctor Who history, and it creates a staggering number of plot holes - especially with the Russell T. Davies and Steven Moffat eras.

But, in truth, showrunner Chris Chibnall has long seemed more interested in staying true to classic Doctor Who than to the relaunch. Indeed, most plots in Doctor Who season 12 have felt more like a traditional four-part episode compressed - with all the attendant strengths and weaknesses. That most likely means Chibnall isn't too concerned about whether or not his retcon aligns with Davies and Moffat; he's drawing inspiration from, and carefully connecting his stories to, the show's rich history.

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Indeed, while the Timeless Child clashes with the continuity of the Doctor Who relaunch - most notably rendering Matt Smith's finale, "The Time of the Doctor," utterly meaningless - it actually builds upon concepts from classic Doctor Who.

Tom Baker's Doctor Who Era Revealed Eight Regenerations Before William Hartnell

Doctor Who The Brain of Morbius

It's important to remember Doctor Who didn't emerge on the TV screens fully-formed. In fact, when the Doctor was first introduced, nobody at the BBC had a clue what the Doctor's background really was. Scripts in the William Hartnell era implied the Doctor had created the TARDIS, and some writers considered the Doctor a human from the future - right up until the moment he regenerated for the first time, settling the issue once and for all. The Time Lords themselves were only introduced in Patrick Troughton's final story, "The War Games," and it wasn't until 1976 that a limit was placed on the number of Time Lord regenerations. That was largely to serve the plot of "The Deadly Assassin," which required the assassination of the Time Lords' president, and writer Robert Holmes fixed on the idea of the cap of 12 regenerations. He did so with no real concern for Doctor Who's future, because it never occurred to him Doctor Who would last so long the Doctor would reach this cap.

Holmes was also involved in the scripting of another 1976 story, "The Brain of Morbius," in which the Doctor confronted a renegade Time Lord named Morbius. The two engaged in a psychic duel, with Morbius attempting to penetrate the Doctor's mind and tear his memories out of his head. "How far, Doctor," Morbius roared. "How long have you lived? Back, back to your beginning…" At the time there had only been a handful of previous Doctors, and a screen showed images of Jon Pertwee, Patrick Troughton, and William Hartnell. The images then continued, displaying eight more faces, apparently in period dress, before the machine exploded.

Producer Philip Hinchcliffe told the Radio Times he definitely intended to suggest there had been other versions of the Doctor before Hartnell. "I just reasoned that it was entirely possible that William Hartnell may not have been the first Doctor Who," he explained. "So yes, as far as [writer] Bob [Holmes] and I were concerned, the other faces were meant to be past Doctors… it is true to say that I attempted to imply that William Hartnell was not the first Doctor."

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Tom Baker's Doctor Who Era Teased Shobogans Becoming Time Lords

Doctor Who Deadly Assassin

Chibnall's Timeless Child retcon - and his rewritten history of Gallifrey - finally explains another mystery from the Tom Baker era. Stories such as "The Deadly Assassin" had implied the indigenous species of Gallifrey were a race called the Shobogans, and the Time Lords were envisioned as Gallifrey's ruling elite. It was a conscious mirror of Britain's old, infamous class system, exaggerated and given a sci-fi edge. The Time Lords lived in the Capitol - a mirror of London - and they possessed both wealth and power that the rest of their race did not. Although Doctor Who has made infrequent mention of the Shobogans, the creation and maintenance of this class system have never been explained - until now.

How Timeless Child Pays Off This 44-Year-Old Mystery

Doctor Who Timeless Child Doctor Master

Chibnall is clearly more attracted to classic Doctor Who than he is to the relaunched series under Davies and Moffat; as such, his Timeless Child retcon is largely designed to pay off this 44-year-old mystery. The past Doctors seen in "The Brain of Morbius" had been forgotten, discounted as an insignificant plot hole, but "The Timeless Child" restores them to continuity. Chibnall even makes a point of subtly referencing it. In one scene in "The Timeless Children," the Doctor uses her memories to mind blast her way out of the Matrix; Chibnall deliberately reuses the memories from "The Brain of Morbius," a smart way of reminding longer-term viewers there's precedent for the Doctor having more than thirteen lives.

Meanwhile, the history of the Timeless Child is also the history of Gallifrey - and its class system. The Master strongly implied Tecteun, the explorer who found the Timeless Child, came from one particular tribe of Shobogans. When she saw the Timeless Child regenerate, Tecteun became obsessed with this power, and ultimately learned how to splice it into her own genes. Now functionally immortal, Tecteun became Gallifrey's greatest scientist, and her particular tribe built the Citadel. This tribe became the self-appointed rulers of Gallifrey, and Tecteun spliced regeneration into the Capitol's inhabitants, ensuring their continued growth and dominance.

Doctor Who's Timeless Child Reveal Also Pays Off The Cartmel Masterplan

Sylvester McCoy is The Doctor

Looking beyond the Tom Baker era, "The Timeless Child" also neatly resolves major plot threads from the 1980s, in the forgotten and neglected "Cartmel Masterplan." Script editor Andrew Cartmel oversaw the writing of Doctor Who from 1987-1989, and he felt the Doctor had become something of a known commodity. Cartmel decided to restore a sense of mystery to the character, He decided the Doctor should be envisioned as a mysterious presence, a secret founder of Gallifrey. As Cartmel explained in Script Editor: The Inside Story of Doctor Who:

"Omega and Rassilon were the founding fathers of Gallifrey. They towered above the Time Lords who followed. They were demigods. [Dialogue in Silver Nemesis was] a subtle attempt to say that there was a third presence there in the shadowy days of Gallifrey's creation. In other words, the Doctor was also there. So he's more than a Time Lord. He's one of these half-glimpsed demigods."

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In "Remembrance of the Daleks," Sylvester McCoy's Seventh Doctor described himself as "far more than just another Time Lord." He made a throwaway reference to the problems the Time Lords had with the Hand of Omega, the remote stellar manipulator that created the Eye of Harmony, key to the development of time travel. "And didn't we have trouble with the prototype," the Doctor reminisced. "We," his companion Ace queried, and the Doctor quickly adjusted to "They." Both "The Curse of Fenric" and "Battlefield" hinted a vast stretch of the Doctor's history was unseen and forgotten; in the latter case, multiple incarnations of the Doctor were revealed to be the truth behind the legend of Merlin, a fact that surprised the Seventh Doctor as much as it did Ace. Finally, in "Silver Nemesis" the sinister Lady Peinforte hinted she knew the Doctor's secrets, ones that were still obscured from viewers. Unfortunately, Doctor Who was cancelled in 1989, and these various hints were only explored in tie-ins now considered non-canon. The Cartmel Masterplan was ignored by Davies and Moffat, understandably so because it could be considered quite obscure by 2005.

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Chris Chibnall's Timeless Child thus fits perfectly with all these obscure hints and plot holes from classic Doctor Who. Of course, in order to make it work you have to assume that different incarnations of the Doctor had varying degrees of knowledge of their past; regeneration is known to scramble the neurons after all. Ironically, Chibnall first began subtly hinting there was more to the Doctor's history than viewers had seen in the episode "Arachnids in the U.K.," when dialogue suggested there had been previous female Doctors. At the time this was seen as something of a plot hole, because it broke the regeneration cap, but it can now be interpreted as a fragment of memory bubbling up in the Doctor's mind, and subsequently repressed. It's now clear Chibnall was laying the groundwork for his Timeless Child retcon all along.

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