Deep 13 was a subbasement of Gizmonic Institute and, according to former SOL janitor Joel Robinson, highly radioactive as a result of being close to the Institute's atomic pile. The Mads worked and eventually took up residence there as well. There was a neighboring Deep 12 whose tenants once included two "foxy ladies."
In the final Comedy Central episode, Dr. Forrester shut down Deep 13 and moved back in with his mother after his funding was cut. The show never explained from whom Forrester was receiving funding. However, series creator Joel Hodgson (who also played Robinson), when pressed in an interview for the Satellite News, gave a plausible explanation: the Mads were selling the show to basic cable providers (effectively making it a show within a show). This storyline was bolstered by several "host segments" from the KTMA season through season 7 that discussed the internal show's ratings. But as Hodgson cautioned in the interview, such storylines should be taken with a grain of salt, as recommended by the show's theme song: "Just repeat to yourself, 'It's just a show / I should really just relax'".
In Season Eight, the Satellite of Love returns from the edge of the universe, mysteriously pulled back to Earth's orbit. When Mike and the Bots attempt to contact Deep 13, they instead find a lab run by intelligent, evolved apes (a parody of the film Planet of the Apes in the year 2525). Though referred to onscreen as "The Lab", offscreen it has been referred to by fans and crew as Deep Ape, as it was the first replacement lair for the Mads after Deep 13. Villains Pearl Forrester and Professor Bobo remained in Deep Ape for four episodes before it was accidentally destroyed by Professor Bobo, along with the rest of the Earth.
|Principal||Dr. Clayton Forrester • Dr. Laurence Erhardt • TV's Frank • Pearl Forrester • Professor Bobo • Brain Guy • Kinga Forrester • Max|
|Secondary||Gerry and Sylvia • Dr. Peanut • The Observers • Synthia • Ardy • Skeleton Crew|
|Mirror Universe||Mike Nelson • Crow T. Robot • Tom Servo • Gypsy|
|Locations||Gizmonic Institute • Deep 13 • Deep Ape • The Widowmaker • Ancient Rome • Castle Forrester • Moon 13|