DOCTOR: Yes, that's the TARDIS. And I'm going to pilot it all the way to London. I can be there five minutes ago.

SARAH: Just a minute, Doctor. I thought you couldn't do that.

DOCTOR: Of course I can. Coming?

BRIGADIER: No, thank you.

HARRY: I think I'll stick to InterCity this time, Doctor.

DOCTOR: Sarah?

SARAH: Er.

DOCTOR: No?

SARAH: All right. Providing we do go straight back to London.

DOCTOR: Oh yes, we will. I promise.