Season Twenty-Six

Nitcentral's Bulletin Brash Reflections: Doctor Who: Classic Who: Season Twenty-Six
'There are worlds out there where the sky is burning, the sea's asleep, and the rivers dream. People made of smoke and cities made of song. Somewhere there's danger, somewhere there's injustice, and somewhere else the tea is getting cold. Come on, Ace - we've got work to do!'

The Master's a cat, the Doctor's Merlin, and the Companion is the pawn of an Evil From Before The Dawn Of Time. Who finally achieves a perfect season, whereupon it is of course cancelled.