(Harry comes out of the TARDIS.)

HARRY: Oh, I say. We've gone!

(Harry looks at the TARDIS)

HARRY: You could sell that thing, Doctor.

DOCTOR: I could what?

HARRY: Jolly useful in Trafalgar Square. I mean, hundreds of bobbies hiding inside it.

DOCTOR: It may be irrational of me, but human beings are quite my favourite species.

DOCTOR: Homo sapiens. What an inventive, invincible species. It's only a few million years since they've crawled up out of the mud and learned to walk. Puny, defenceless bipeds. They've survived flood, famine and plague. They've survived cosmic wars and holocausts, and now here they are amongst the stars, waiting to begin a new life, ready to outsit eternity. They're indomitable. Indomitable!

HARRY: She's coming round.

DOCTOR: Good.

HARRY: Steady. Steady on, old girl. Steady on.

SARAH: Harry

HARRY: Yes, I'm here, I'm here.

SARAH: Call me old girl again and I'll spit in your eye.

DOCTOR: Welcome back, Sarah Jane.