The Timeless Child is the biggest mystery of Doctor Who season 12 - and here's everything we know about her to date. Chris Chibnall's first season as showrunner didn't really have much of a central theme; although the Stenza were a recurring threat, each episode still felt like a standalone.

For all that's the case, though, there were subtle hints as to the scale of Chibnall's vision. He clearly intends to rewrite Doctor Who's lore to some degree. Chibnall introduced Time Lord religion with a Gallifreyan creation myth; he added a line of throwaway dialogue hinting the Doctor had been female before; and, most notable of all, there was a reference to a mysterious "Timeless Child."

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But just what is the Timeless Child? This was obvious foreshadowing, with the Timeless Child set to become key to Doctor Who season 12 thanks to the events of "Spyfall - Part 2". So let's explore everything we know about her.

The Timeless Child Was First Mentioned In Doctor Who Season 11

Doctor Who Season 11 Ghost Monument Timeless Child

The Timeless Child was first mentioned in Doctor Who season 11, episode 2. In one scene, the monstrous Remnants - dangerous ribbon-creatures - attempted to frighten the Doctor by peering into her mind. The freshly-regenerated Doctor proved unusually vulnerable to psychic manipulation, and the Remnants were able to dig into her greatest fears. "We see... further back," the Remnants whispered. "The Timeless Child… we see what’s hidden, even from yourself. The outcast, abandoned and unknown…" The mention of the Timeless Child left the Doctor dumbstruck with shame and fear, and the reference prompted her to push the Remnants out of her mind.

The Timeless Child Is Doctor Who Season 12's Big Mystery

Doctor Who Jodie Whittaker Face

It's now clear that the Timeless Child is the greatest mystery of Doctor Who season 12. Last season's reference was a blink-and-you'll-miss-it moment, easy to forget, even easier to overlook; frankly, it looks as though the Doctor herself tried to put it out of her mind. But she won't be able to do so now, because the Timeless Child has been linked to the destruction of her homeworld and an act of genocide that has left her as possibly the last of the Time Lords. For now, the Doctor seems to be internalizing her grief, but it's only a matter of time before she's spurred into action. The Master has confirmed that it's possible to discover the truth about the Timeless Child, and the Doctor will want to do just that.

The Timeless Child Is The Time Lord's Biggest Secret

Sacha Dhawan as Master and Jodie Whittaker as Thirteenth Doctor in Doctor Who

According to the Master, the Timeless Child is the dark secret at the heart of Time Lord history, systematically erased from all records. "They lied to us," he told the Doctor, sounding mournful and shaken at whatever he had discovered. "Everything we were told was a lie. We are not who we think. You or I. The whole existence of our species - built on the lie of the Timeless Child." It shouldn't really come as a surprise to learn that Time Lord civilization was built upon a falsehood; the Doctor's race have always had a propensity for lies. But this secret appears to be of an entirely different scale; it looks to be key to the Time Lords' power or prominence, perhaps to their discovery of time travel or regeneration - possibly even both. The Master made reference to Gallifrey's "founding fathers," presumably indicating Rassilon and Omega.

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This isn't the first time Doctor Who has hinted that a secret has been concealed in Time Lord history. In the 1980s, Doctor Who script editor Andrew Cartmell planted hints that there had been a third founding father of Gallifrey, the Other, and began to allude to the possibility that the Doctor himself was the Other. The classic series was canceled in 1989, before the plot was developed. It could be that the Timeless Child is related to this; of course, it's also possible Chris Chibnall will choose to completely ignore somebody else's story, especially an unfinished one.

In Doctor Who season 12, episode 2, it's suggested that every Time Lord has inherited a race memory of the Timeless Child. The Remnants must have accessed that race memory when they taunted the Doctor in season 11, and it's possible the Master used this as the key to unlocking the truth of Time Lord history. If that is the case, then the Doctor could need to subject herself to severe psychic trauma if she's going to learn more about the Timeless Child.

The Master Destroyed Gallifrey Over The Timeless Child

Doctor Who Gallifrey Destroyed

Whatever the Timeless Child may be, discovering this ancient truth left the Master completely outraged. He returned to his homeworld of Gallifrey, in itself quite a remarkable feat, and wiped out his own race in what he claimed was an act of vengeance. It's a pretty extreme reaction even for the Master, who has personally uncovered many of Gallifrey's darkest secret in the past, and who typically prefers to exploit them to his own advantage. The Master seems to have taken this particular lie personally, as though it was directed against him individually - and, perhaps, also against the Doctor. "We are not who we think," he told the Doctor. "You or I."

Of course, it shouldn't be assumed that the Master was being entirely honest in what he told the Doctor. It's possible the Master destroyed Gallifrey as part of his quest, and that the planet was ravaged as a side-effect of his learning the truth of the Timeless Child. If that is the case, then the Doctor will need to return to Gallifrey, and she will find clues among the Citadel's ruins.

Related: Doctor Who: Why The Master Destroyed Gallifrey

What The Timeless Looks Like Doctor Who Season 12

Doctor Who Timeless Child

The Master's words unlocked the Doctor's race memory, and she received a vision of the Timeless Child. She seems to be a young girl with dark skin, clad in what appear to be Gallifreyan robes, and standing outside a citadel. The architecture is similar to that of Gallifrey, with a towering spire, but it's not identical. It may be early Gallifreyan, predating the rise of the Time Lords, or it may be a related world. Whatever the case, of course, it's far from clear that the Timeless Child will still look like this now; millennia have passed since the time of Rassilon and Omega, so she will have changed and aged over time. Indeed, it could be that the Doctor has already encountered her; if the Timeless Child possesses the power of regeneration, she could take on any appearance at all.

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