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
Before the Flood (Doctor Who) convinces Cass and Lunn to admit their love for each other. As they leave, Clara asks about the origin of the list of names he had his ghost repeat, to which the Doctor replies "Who composed Beethoven's Fifth?" In the prologue, the Doctor performs Beethoven's Symphony No. 5 with his electric guitar. The Doctor had previously been shown playing such an instrument atop a tank in the ninth series opener, "The Magician's Apprentice". The electric guitar amplifier seen in the Doctor's prologue has a plaque reading Magpie Electronics, a shop originally owned by Mr Magpie and visited by the Tenth