• Captain Hazel "Hank" Murphy (voiced by
Harry Goz) is the ostensible leader of the crew, though his qualifications, and even his grasp on reality, are questionable. He is generally found loitering on the bridge, neglecting his duties. Murphy spends his time participating in scams and juvenile antics, generally causing problems that the crew has to solve. Murphy is a parody of Captain Mike Murphy from
Sealab 2020. Generally, Murphy is incapable to the point of incompetence. After the death of Harry Goz, Murphy was written out of the show by having him leave Sealab to fight in the "Great Spice Wars". Murphy later appeared in the Reed and Thompson-created series
Archer, where he was voiced by
Jon Hamm and debuted in the two-part episode "Sea Tunt". • Captain Bellerophon "Tornado" Shanks (voiced by Michael Goz) is a retired football coach and health and hygiene teacher who lost his job for slapping (or throat punching) a student. He answered Sealab's help wanted ad and became the new captain, despite having no experience whatsoever. Shanks is from Texas and is the youngest of several brothers all named after characters in Greek mythology, and all of whom met their death on or around a bridge in Shanks's hometown. Shanks is much more self-aware than Murphy, openly commenting on the odd goings-on aboard Sealab and even the fact that he is on a television program. Since Shanks has no experience or idea what he is doing, he goes along with whatever the rest of the crew suggests, usually with disastrous results. • Lieutenant Jodene Sparks (voiced by
Bill Lobley) is a commander and radio operator who is always seen sitting with his headsets on. Sparks is a parody of Lieutenant Sparks from
Sealab 2020. Sparks mostly uses the radio for his own personal purposes, even going so far as to disconnect vital transmissions that interrupt him. He generally travels around in his office chair, mostly because he is lazy, even though it was suggested that he is crippled. Sparks is a convict serving time at Sealab while still operating a black market distillery and takes part in a wide variety of other illegal activities. He occasionally serves as a voice of reason to the crew, particularly to Murphy. • Debbie "White Debbie" DuPree (voiced by Kate Miller) is a lieutenant commander, marine biologist, and one of only two adult women on the base. Serving as a parody of Gail from
Sealab 2020, she is a blonde and is often the object of the sexual interest of the males on Sealab. She has an ongoing sexual relationship with Doctor Quinn, and their relationship, its ups and downs, and its effect on the rest of the crew play out in several stories. This does not stop the other males, particularly Stormy, from attempting to get on her good side. Debbie's mood swings are a constant issue to the crew, as she changes wildly from the sole voice of reason to a shrieking lunatic. • Derek "Stormy" Waters (voiced by
Ellis Henican) is a lieutenant commander lacking in intelligence or seemingly any qualifications to be working on a government research lab, and a parody of Hal from
Sealab 2020. Stormy's job is never clearly defined and he usually walks around Sealab doing whatever he wants or acts as a henchman or assistant to whomever he is nearest. Stormy usually works alongside Quinn, who is frequently the victim of Stormy's ignorance, but ironically is the crew member who's most tolerant of him. • Dr. Quentin Q. Quinn (voiced by Brett Butler) is a lieutenant commander and science officer. Parodying Ed from
Sealab 2020, he is an extremely intelligent African-American with an IQ of 260 and Ph.D.s in several scientific disciplines, of which he is not shy about reminding the other characters. Quinn grew up in unbelievably over-the-top poverty and got to where he is through hard work, unlike the majority of the other characters. He is regarded as an uptight killjoy by most of the crew. Quinn is often the only responsible crew member and the sole voice of reason. Despite his intelligence, Quinn is extremely vain and prone to outbursts of anger when he is not appreciated. • Marco Rodrigo Diaz de Vivar Gabriel Garcia Marquez (voiced by
Erik Estrada) is a lieutenant commander and engineer. Spoofing Dr. Paul Williams from
Sealab 2020, he is very strong and muscular, unlike the rest of the crew. He speaks with a Spanish accent and often exclaims random things in Spanish, although not actually speaking the language. His name is derived from literary character
Rodrigo Díaz de Vivar and writer
Gabriel García Márquez. • Hesh Hepplewhite (voiced by
MC Chris) is a lieutenant and reactor operator. Nasal-voiced, smart-mouthed, and whiny, Hesh is not well-liked by most of the crew and thus works in the part of the station farthest away from them. He has no real understanding of how the reactor works and generally has to have guidance from Quinn when there is a problem. • Debbie "Black Debbie" Allison Love (voiced by
Angela Gibbs) is an African-American lieutenant who is a parody of the
Sealab 2020 character Mrs. Thomas (Ed Thomas's mother). She teaches school to the Sealab's orphans and is very proud of her race. She has a relationship with Marco at the beginning of the show and briefly dates Sparks and Tornado in the later seasons. • Dr. Ilad Virjay (voiced by
Adam Reed) is the station's official doctor and in-house surgeon noted for his thick Indian accent and relatively normal personality. He graduated third in his class from the Medical College of Mescutabuti. He practices Manduism, the Sealab universe's version of
Hinduism. Virjay is shown to be jealous of Dr. Quinn as the latter has multiple Ph.Ds and a higher IQ. • Dolphin Boy is a little chubby boy who speaks in
dolphin noises. One of the orphans that inhabit Sealab for some reason, he is a member of Black Debbie's class. Dolphin Boy often wanders around the station and, as a result, is often embroiled in whatever is going on. When translated, Dolphin Boy generally says inoffensive, naively childish statements, universally resulting in derision and hatred from the rest of the crew. • Sharko (voiced by
Matt Thompson) is a half-human, half-shark freak of nature who is the result of Marco having sexual relations with a shark. • The Five Jew Bankers are a lampoon of Jewish conspiracy theories. They are introduced in the third-season episode "Neptunati". ==International broadcast==