MONK: I’m happy to do my bit to stop him destroying the future.

HELEN: Oh, that’s what I don’t understand. The future isn’t destroyed - we’ve been there. Liv comes from the future!

MONK: As with most things in a temporal nexus, things don’t happen until they do. Are you familiar with the term “Pit Canary”?

LIV: Did the Doctor go to school with anyone who didn’t turn out to be a Time Lord Super Criminal?!

DOCTOR: Round and around, like a snake eating its own tail

HELEN: Ouroboros?

DOCTOR: Bless you.

OLLISTRA: My work is not finished. Gallifrey… Gallifrey…

(Ollistra regenerates)

OLLISTRA: Gallifrey Must Stand.