Host
Conrad Earp
Augie Steenbeck
Woodrow
Midge Campbell
Dinah
June
Montana
General Gibson
Sandy Borden
Roger Cho (as Stephen Park)
J. J. Kellogg
Clifford
Ricky
Shelly
Stanley Zak
Andromeda
Pandora
Cassiopeia
Waitress
Cashier
Cook
Mechanic
Romulus
Bus Driver
Chaperone
Bernice
Billy
Dwight (as Preston George Mota)
Other Pupil
Other Pupil (as Henry Sebastian Rhoades)
Other Cowboy
Bodyguard / Driver
Motel Manager
Motel Handyman
Conrad Earp's Secretary
Aide-de-Camp
Larkings Executive
Detective #1
Detective #2 (as Mike Maggart)
Dr. Hickenlooper
Mary
Military-Science Ensign
Stunt Double (as Katy Heffernan-Smith)
The Alien
Schubert Green
Lunky
Polly
Telephone Booth Guard
Mrs. Weatherford
Skip Weatherford
Saltzburg Keitel
Newsboy
Actress / Wife
Backstage Sound Man
Engineer
Pilotman
Brakeman (as a different name)
Hobo
Caddy
Outlaw on the Run
Outlaw on the Run (as Pablo Amoros)
State Trooper
Cameraman
Motel Guest (at Shower)
Motel Gardener
Motel Maid (as Ana Isabel Comendador Martínez)
T-Shirt Vendor
Bookseller
Man with Soda
Hot Dog Stand
Girl on Blanket
Souvenir Booth (as Milagros Ahijón)
Souvenir Booth
Boy in Spacesuit
Ferris Wheel Crew
Other Actor / Student
Actor / Student
Scientist
Scientist / Military-Science Officer
Train Porter
Seamstress
Recording Secretary
Military-Science Officer
Military-Science Officer (as Oscar Minguez Garcia-Patron)
Military-Science Guard
Parent on TV Screen
Parent on TV Screen (as Erika Leigh Godwin)
Chaperone 2 (uncredited)