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
Great Intelligence to destroy the Intelligence. However, the Great Intelligence has existed long enough to become an independent entity and uses Simeon's brain-dead husk to attack the Doctor before withdrawing from his vessel when the Latimer family cries for the dying Clara, triggering his snow to melt. It is implied these events lead to "The Web of Fear" as the Doctor shows a map of the London Underground from 1966 to the Great Intelligence. The Great Intelligence appears in the 2013 episode "The Bells of Saint John", set in the present day. The Great Intelligence uses a woman called Miss Kizlet (Celia