DOCTOR: His heartbeat's slow but steady as a drum. An hour's rest, he'll be right as rain, whatever that means. An hour. An hour to kill. How to turn it to account? We must make plans, Peri. My full powers are returning.

PERI: Plans? Do you think that wise?

DOCTOR: My perception's sharpening. I can sense some massive danger threatening the universe.

PERI: I thought you were the danger to the universe.

DOCTOR: Me?

PERI: That's what you said. That's why we came here, so that you could meditate.

DOCTOR: Words spoken in the sickness of transition. Now, there is a sickness in the air. I can feel the vibrations. I cannot yet detect their source, but it is there. I am never wrong. The life force itself is in danger of extinction. We must find this evil and destroy it.