13 Darkest Doctor Who Endings Ever

The ending of The Waters of Mars shows us just how dangerous the Doctor could be without rules. This is the closest we ever get to the Doctor being the antagonist of an episode, and seeing him play god is chilling.

What starts off as a formulaic (but still excellent) base-under-siege story pivots aggressively with the reveal that everyone on Bowie Base One is doomed to die, and worse yet, that their deaths are fixed points in time. The Doctor is forced to walk away as these people he respects and admires are picked off one by one in brutal fashion... until something in him snaps.

No one is forcing him to play by the rules anymore. So he returns, risking the future of the human race, and saves Adelaide, Yuri, and Mia – not out of compassion, but simply because he can. More than that, he absolutely revels in doing so, and is borderline unhinged.

Back on Earth, Adelaide sees what the Doctor has become, and his dialogue paints him, in no uncertain terms, as the villain. Realising her death still needs to happen to keep history intact, Adelaide calmly enters her home, and takes her own life. It’s a truly shocking move from a show like this and it leaves the audience reeling. Our protagonist has forced these horrible circumstances on Adelaide to feed his own ego, and almost robbed her of her dignity in death.