After the battle with Vilgax, Grandpa Max retells his story to Ben about his past. He was with an organization that was not known to exist, referred to as "The Plumbers," a group of people who track down extraterrestrial life. Meanwhile, they meet Phil, an old partner of Grandpa Max. But they soon find out that he steals a device, called the Null Void Projector, to selfishly use it to make money by appearing to capture aliens that he alone released himself.
Elenco: Ashley Johnson , Charlie Schlatter , Dwight Schultz , Greg Cipes , Greg Ellis , Jeff Bennett , Jim Ward , John DiMaggio , Kevin Conroy , Kevin Michael Richardson , Michael Dorn , Peter Renaday , Richard Green , Rob Paulsen , Robin Atkin Downes , Tom Kane , Vicki Lewis , Yuri Lowenthal , Jennifer Hale , Kari Wahlgren , Khary Payton , Tara Strong , Claudia Schmidt , Meagan Smith , Paul Eiding , Ulf Söhmisch , Dee Bradley Baker , Fred Tatasciore , Richard McGonagle , Richard Steven Horvitz .