10 Doctor Who Episodes Where Evil Won

Evil may be a strong word for it, but the darkest impulses of both humans and lizards ultimately win out in Cold Blood.

The scared and vengeful Ambrose tortures Alaya to death with a taser, desperate to find a cure for her father's condition and reunite with her Silurian-napped son. This murder effectively scuppers any hope that the Doctor has to finally negotiate peace between the humans and their Earth-mates.

The Doctor even angrily confronts Ambrose and reveals he's disgusted by her behaviour, a rare moment for the man who so often sings humanity's praises, even when the chips are down.

Alaya's sister Restac swears revenge on Ambrose and her fellow humans, peace talks descend into chaos, and the Doctor is forced to hastily send all of the Silurians back into hibernation. To top it all off, Restac guns down Rory, leaving him to be erased by an inconveniently-placed crack in space and time.

All of this means that by the end of Cold Blood, paranoia and xenophobia have won the day, destroying any chance of harmony between humans and Silurians for at least another century.

Unless of course The War Between the Land and the Sea finally gives the two sides a peaceful resolution!