DOCTOR: Small though it is, the human brain can be quite effective when working at full efficiency.

DOCTOR: Your Doctor is an antediluvian fogey. Allowing himself to be captured by the Sontarans. If anything happens to myself as a result of it I will never forgive himself.

PERI: Oh, I do wish you'd stop switching personal pronouns. It'd make it a lot easier to understand what you're talking about.

PERI: And what did it mean, defence alert?

DOCTOR: (sighs) The usual. Floor trips, electronic sensors, death rays, jets of nerve gas. Nothing to worry about.

PERI: Oh, good. I was afraid it might mean something serious.