Earl Sinclair
Stuart Pankin
Fran Sinclair (voice)
Jessica Walter
B.P. Richfield (voice)
Sherman Hemsley
Roy Hess (voice) / John (voice) / Absolute Proof Laboratories Scientist (voice)
Sam McMurray
Robbie Sinclair
Jason Willinger
Charlene Sinclair (voice)
Sally Struthers
Baby Sinclair
Kevin Clash
Grandma Ethyl
Florence Stanley
Gary
Steve Landesberg
Mel Luster
Richard Portnow
Arthur Rizzic
Brian Henson
Dinosaur Chief
Harold Gould
Mr. Ugh
Michelan Sisti
Monica Devertebrae (voice) / Thighs of Thunder (voice) / Elder #3 (voice)
Suzie Plakson
Mr. Pulman (voice) / Monster (voice) / Dr. Elliot Piaget (voice)
Allan Trautman
Guy in the Lab Coat (voice) / Bryant (voice) / Police Chief Parish (voice)
Michael McKean
Spike (voice)
Christopher Meloni
Chef (voice) / Ed (voice) / Richard (voice)
Thom Sharp
Mindy (voice) / Sitcom Wife (voice) / Vendor (voice)
Jessica Lundy
Gus Molehill (voice) / Stu (voice) / The Job Wizard (voice)
Jason Alexander
Fox Jacket (voice) / Henri Poupon (voice) / Pterodactyl (voice)
Tim Curry
WeSaySoCorp Announcer (voice) / Television Announcer (voice) / Elder in Chief (voice)
Michael Dorn
Timmy (voice) / Wereman (voice)
Kirk R. Thatcher
Narrator (voice)
Gary Owens
News Bulletin Announcer (voice) / USO Stage Manager (voice) / TV Announcer (voice)
Chuck Varesko