10 Darkest Endings In Doctor Who
6. The Waters of Mars (2009)
With his regeneration only two episodes away, this story sees the Tenth Doctor go mad with power after initially refusing to save the crew of Bowie Base One, who are all destined to die on Mars the very same day he arrives. It’s a fixed point in time and can’t be altered. Or can it?
In a moment of righteous fury, the Doctor decides that, since he’s the only Time Lord left in the universe, there’s nothing to stop him from saving everyone and changing history. The laws of time are his. After bringing the three survivors of Bowie Base’s destruction back to Earth, the Doctor proudly declares his new delusions of godhood to Adelaide Brooke, the base’s captain. She is disgusted, point blank telling him that he was wrong to alter the course of history like that.
In order to restore the timeline, she walks quietly into her home and commits suicide by gunshot. The Doctor realises that he’s gone too far and has let his darkest impulses take over. He is forced to face what he’s become after travelling on his own for far too long, and it’s not a pretty sight. This is an episode where the line between heroism and villainy is blurred to chilling new levels, and the Tenth Doctor never fully recovers from it.