Richard Eyer
饰 Timmie Merrinoe
Philip Abbott
饰 Dr. Tom Merrinoe
Robert H. Harris
饰 Prof. Frank Allerton
Dennis McCarthy
饰 Col. Macklin
Alexander Lockwood
饰 Arthur Kelvaney
John O'Malley
饰 Prof. Baine
Gage Clarke
饰 Dr. Bannerman
Than Wyenn
饰 Prof. Zeller
Jefferson Dudley Searles
饰 Prof. Foster
Alfred Linder
饰 Martin / Computer
Ralph Votrian
饰 1st Gate Sergeant
Michael Miller
饰 2nd Gate Sergeant
Rayford Barnes
饰 Capt. McLaren (uncredited)
Helen Kleeb
饰 Miss Vandergrift (uncredited)
Alvy Moore
饰 Scientist (uncredited)
Gary Vinson
饰 Young soldier (uncredited)
Marvin Miller
饰 Robby the Robot (voice) (uncredited)
