(The Doctor and Adric enter the TARDIS)

DOCTOR: Well, she seems to be going right as ninepence now.

ADRIC: Why couldn’t I start it?

DOCTOR: Oh, probably the Master up to one of his little party tricks again. Then the general run-down condition. It badly needs an overhaul.

ADRIC: Then why don’t you?

DOCTOR: Well, it involves an awful lot of recalculation, and this type’s not really my forte.