Season 5

As it turns out Sealab was built on an ancient Indian burial ground and is now sinking into the ocean floor. The only hope to save Sealab is John Bear, Sealab's resident Native American. But in order to save Sealab Shank's must agree to turn the Mess Hall into a casino which he does. But once the casino opens John Bear still won't stop the sinking (or let Debbie have a lounge show).

Marco convinces Debbie to give up her "questionable" ways through a pep talk, leading her to find religion and dump Quinn. Meanwhile, Sparks recognizes the pep talk from a 60's show, which leads a drunken Quinn to sic the network on the fugitive TV star Marco.

Extreme rebel trillionaire, Max Stone, buys Sealab and ends up running it better than before.

The police want Shanks... Why? The story is revealed in reverse. But it involves a monster, a plan to improve the world, and Grizzlebee's.

Quinn and Stormy are stuck in a cave with only 10 minutes of oxygen while sealab burns.

Abalon, a terminally ill whale, comes to Sealab and asks Doctor Quinn to kill him. While Quinn wonders whether or not he could end a life Stormy recognizes Abalon as the star of a show called ‘I Gotta Have That Dick' and starts bugging him with fan fics. While Quinn examines Abalon's whale cancer Marco accidentally eats some of it and is inspired to create his own drink called F-YEAH!

All the water around Sealab has disappeared, and left Sealab high and dry. Where has it all gone?

The cast looks back over five years of "A Legacy of Laughter" in the style of one of those tacky TV reunion specials but of course since this IS Sealab, not all goes well.