I know it sounds crazy, but this is my comfort episode of Doctor Who. I could watch it a billion times and it would never get old.

It distilled everything I love about Doctor Who: first off it's an awesome genre mash-up between history, classic literature, and sci-fi. It's a dark, dramatic story with Peter Capaldi at his acerbic best. The relationship between him and Clara is taken almost to its limit. The denouement is heart-pounding and thrilling, and there are twists throughout.

If somebody asks me what I love about Doctor Who, I'd show them Mummy on the Orient Express.