Doctor Who: Every Doctor's DEFINITIVE Episode

Not only is this two-parter utterly iconic, but for Nine’s character, it’s an important beat in his arc – this is the point where the Doctor finally starts to forgive himself for the Time War.

Up until this point, Nine is angry, sharp-edged, and visibly traumatised. He’s the PTSD Doctor, carrying the weight of a double genocide on his back. He is a man who has lost everyone, but in this story, in spite of the hopeless situation he faces, Nine is able to save everyone.

In another episode this might feel like cheating and could very easily undercut the stakes. In Nine's case, however, he needs this win so badly that this moment, instead of being a cop-out, is one of pure euphoria.

"Everybody lives!" is the emotional apex of Nine’s arc, and it’s not just any old victory. For the first time since the war, the Doctor saves the day without any compromise or trade-off, and the episode makes sure that this ‘flawless victory’ is well-earned. The bleak horror tones of the rest of the script cleverly frame this ending as a twist, because at no point does it look like it's heading in that direction (this Moffat bloke is pretty good, they should get him to write some more).

Then comes the gas mask child, the creature responsible for many childhood nightmares across the country. This two-partner also introduces Captain Jack Harkness, and nobody needs to explain why that makes it an instant classic!