Episode 4 The Power of Three

The Doctor: Invasion of the very small cubes. That's new.

Brian: What if they're bombs? Billions of tiny bombs. Or transport capsules, maybe, with a mini-robot inside. Or deadly hard drives. Or alien eggs. Or messages needing decoding. Or... they're all parts of a bigger whole. Jigsaw puzzles that need fitting together.
The Doctor: Very thorough, Brian. Very, very thorough. Well done. Stay here. Watch these. Yell if anything happens.

Rory: What do you think we do when we're not with you?
The Doctor: I imagine mostly kissing.

Rory: There are soldiers all over my house and I'm in my pants.
Amy: My whole life I've dreamed of saying that. And I miss it by being someone else.

Rory: You said we had to be patient.
The Doctor: Yes, you. You, not me. I hate being patient. Patience is for wimps.

Amy: Secret base beneath the Tower. Hope we're not here because we know too much.
Kate: Yes, I've got officers trained in beheading. Also ravens of death.
Amy: I like her.

The Doctor: I need to think, I need some air. Who has an underground base? Terrible ventilation.

The Doctor: I'm not running away. But this is one corner, of one country, on one continent, on one planet, that's a corner of the galaxy, that's a corner of the universe that' is forever shrinking and growing and destroying and never remaining the same for a single millisecond. And there is so much--so much to see, Amy. Because it goes so fast. I'm not running away from things, I'm running to them before they flare and fade forever.

Amy: And why do you keep coming back for us?
The Doctor: Because you were the first. The first face this face saw. And you are seared onto my hearts, Amelia Pond. Always will be. I'm running to you and Rory before you... fade from me.
Amy: Don't be nice to me. Don't want you to be nice to me.
The Doctor: Yeah, you do, Pond. And you always get what you want.