DOCTOR: It's funny, cos I wonder where the TARDIS goes at random. Maybe it lands on some outcrop by the sea. And there's a tribe and they worship it for 100 years. Then they grow up and try to burn it. Then they get wise. They preserve it. Then they build a city all around it, till the TARDIS is just a tiny little dot, surrounded by skyscrapers and monorails. Time passes and the city falls. It all gets swept away. And there's the TARDIS… still on its outcrop… by the sea. She's the only thing I've got left.

DOCTOR: There are worlds out there where the sky is burning, where the sea's asleep, and the rivers dream. People made of smoke, and cities made of song. Somewhere there's danger, somewhere there's injustice, and somewhere else the tea's getting cold. Come on, Ace, we've got work to do!

DOCTOR: A straight line may be the shortest distance between two points, but it is by no means the most interesting.

DOCTOR: You know, I am so constantly outwitting the opposition, I tend to forget the delights and satisfaction of the arts, the gentle art of fisticuffs.