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 Name of the Doctor of the Doctor's prior incarnations is used during scenes in which Clara and the Great Intelligence interact with the Doctor. Footage of the First (from "The Aztecs", 1964, with dialogue from "The Web Planet", 1965), Second, Third (both from "The Five Doctors", 1983), Fourth ("The Invasion of Time", 1978), Fifth ("Arc of Infinity", 1983), and Seventh ("Dragonfire", 1987) Doctors was shown. Stunt doubles were used for some other brief appearances, including the Sixth Doctor walking past Clara while she is in a corridor. The Ninth Doctor can also be seen running past her in the Doctor's time stream. The opening