Warning: The following contains SPOILERS for Doctor Who “The Timeless Children.”

The final scene of Doctor Who’s season 12 finale, “The Timeless Children,” may have introduced a major continuity error into the show regarding how the defenses of the TARDIS work. This would prove ironic if that’s the case, given how much of “The Timeless Children” was devoted to reconciling several plot holes from the classic series.

The central plotline of Doctor Who season 12 centered around The Doctor’s archenemy The Master destroying the Time Lord homeworld of Gallifrey, after discovering a dark secret tied to a figure known as The Timeless Child. The season finale revealed that The Timeless Child was an alien being, discovered and adopted by a Gallifreyian explorer and scientist named Tecteun. The Timeless Child was later revealed to be seemingly immortal, regenerating a new body any time they suffered a mortal injury. Tecteun experimented on the adoptive child and isolated the secret of their immortality on a genetic level, granting the Time Lords the power of regeneration. The Timeless Child was also revealed to be The Doctor, whose memories of their true past had been altered by the Time Lords.

“The Timeless Children” ended with The Doctor separated from her companions. Shortly after returning to the TARDIS, The Doctor was ambushed by a group of Judoon, a species of mercenary peacekeepers who resemble humanoid rhinos. Before she had a chance to protest, The Doctor was forcibly teleported to a small prison in the middle of deep space to serve a life sentence for an unspecified crime. As thrilling as this climax was, it was also impossible based on everything that is known about the TARDIS and its ability to shield itself from unwanted company.

While the TARDIS is largely praised for its ability to travel anywhere in time and space, it has a number of other features that make it notable. Chief among these are its defensive features, which make it all but impregnable to invasion and a virtual fortress. The Ninth Doctor once boasted to his companion Rose Tyler that the assembled hordes of Genghis Khan couldn’t force their way into the TARDIS and they had, in fact, attempted to do so. The TARDIS had even thwarted the efforts that technologically advanced species such as the Daleks and the Cybermen had made to break into it. The TARDIS also has an Internal Weapons Deactivation System, which is meant to stop any kind of weapon or hostile technology from being used while inside the TARDIS control room.

This begs the question: how did a group like the Judoon, who are known primarily for being dumb muscle, manage what The Doctor’s greatest enemies couldn’t? Presumably an explanation will be provided in the 2020 Doctor Who holiday special. Hopefully it won’t be something simple yet silly like The Doctor hadn’t had a chance to turn it on yet.

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