11. The Beast Below
Right up until the end twists, this episode is among the scariest pieces of television I've ever seen. Why did the elevator eat a child? What are the freaky three faced clown statues? Why is everyone so sad? Why the heck is the ship without engines, and how can it not be connected to anything? What the heck is happening in this freaky future England? Bit by bit, the secrets are revealed. The amazing thing is that each clue seems to make the sum of the mystery more scary. The masked woman is a queen, one who doesn't know how her ship is flying. Every single man and woman on the ship are privy to a secret that they chose to forget, a secret so terrible that Amy was desperate to keep it from the Doctor. And the freaky clown statues can walk and, if they choose, kill you if you protest. The "space whale" ending was not a good choice. Look how it turned out on Torchwood: they made the best of it on Doctor Who. But right up until the whale thing, it was creepy as heck.