Synopsis: Ace has nearly destroyed the TARDIS. The Doctor is forced to make repairs. He throws himself into the project, completely ignoring Ace. She therefore goes off to the TARDIS console room at uses the ship's computers to effect repairs of her own. Studying a map of the TARDIS on the scanner, she watches in awe as the old "police box" apparently restructures itself.
Chief among the changes is the disappearance of her room. The process seems to be out of control, so she sets off into the heart of the TARDIS, looking for the Doctor. He eventually finds her, though, and explains that he set the ship on "automatic reconfigure", so there's nothing to worry about.
She can't help but wonder if the deletion of her room is the TARDIS' not-so-subtle hint that it's time for her to leave . . .