River Song: Right, I have questions. But number one is this: what in the name of sanity have you got on your head? The Doctor: It's a fez. I wear a fez now. Fezzes are cool.

Never ignore a coincidence. Unless you're busy, in which case, always ignore a coincidence.

Well we've moved through the funfair a bit – we've done the rollercoaster, now we're on the ghost train.

I know this is going to sound very self-serving, and I apologize for it, but if you can write comedy, you can pretty much write anything, because it's the hardest. It's the most technically demanding, the most precisely evaluated form of writing. People know if it works or not. There's a big button marked 'fail,' and that's when nobody laughs.

I absolutely love television, and I don't mean to be vulgar, but as I keep having to explain to people from the movie industry, I get more power and more money doing television, so why on earth would I do a film?

Rose: 'If you are an alien, how come you sound like you're from the north?' Doctor: 'Lots of planets have a north!

Sherlock Holmes can be wise and funny. He wasn't, at the beginning. But later on, he's got a bantering relationship with loads of people. He's got a wisdom that he didn't have in the early stage. But he stays on the mountain top, and he will die up there. He's not going to change that.