Paradise Towers two elderly residents ("rezzies") live. Tilda and Tabby explain that all the able-bodied men left the Towers to fight a war, leaving behind only children and the elderly. The only other man still loose in the Towers is Pex, a would-be hero, who appoints himself Mel's guardian. At the Caretaker control centre, the Doctor meets the Chief Caretaker, who greets him as the Great Architect, designer of Paradise Towers, and then promptly calls for him to be killed The Doctor cites an imaginary rule from the Caretakers' manual, confusing them enough to make his escape. Mel and Pex meanwhile have
The Master (Doctor Who) as a recurring villain. He first appeared in "Terror of the Autons" (1971). The Master's title was deliberately chosen by producer Barry Letts and script editor Terrance Dicks because, like the Doctor, it was a title conferred by an academic degree. The brief given in a sketch of the three "new characters" for 1971 (the other two being Jo Grant and Mike Yates) suggested he was conceived to be of "equal, perhaps even superior rank, to the Doctor". Barry Letts had one man in mind for the role: Roger Delgado, who had a long history of screen villainy and had