A Native American promises to save Sealab,which is in danger of crashing into an ancient American Indian burial ground, in exchange for the construction of a casino in the vessel's mess hall.
Quinn creates a hybrid crustacean to reproduce enough larvae as a way to end world hunger, but was thwarted by Grizzlebee's corporate agents (via Sparks) and Captain Shanks. This is presented in a reverse narrative.
Quinn is faced with a dilemma after being approached by a well-known talking whale named Abelard, who is terminally ill from asbestos-causing "whale cancer".
The water surrounding Sealab suddenly disappears and none of the crew members know why. Debbie Dupree, feeling shut out by her male colleagues, conducts her own investigation.
The series finale done as an interview special, including a Q&A session with the actors and/or characters. There's also a tribute to Harry Goz who voiced Captain Murphy until his death in 2003.