Peter Graves
— James Phelps
Martin Landau
— Rollin Hand
Barbara Bain
— Cinnamon Carter
Greg Morris
— Barney Collier
Peter Lupus
— Willy Armitage
David Sheiner
— Colonel Ziegler
Lee Meriwether
— Anna Rojak
Milton Selzer
— Dr. Erich Rojak
George Fisher
— Major Strat
Jack Donner
— Captain Praedo
George Sperdakos
— Dr. Dromm
Ray Baxter
— Alexander Ventlos
Paul Lukather
— Lieutenant
Martin Kosleck
— General
Jack Denbo
— Reporter #1
Walter Alzmann
— Elevator Guard
Bruce Mars
— Sergeant
Gene Benton
— Dr. Taber
Albert Cavens
— Guard (uncredited)
George Hickman
— Janitor (uncredited)
Bob Johnson
— Person on Tape (voice) (uncredited)
Bert Kramer
— Routine Guard (uncredited)
Joe Ploski
— Reporter (uncredited)
Leoda Richards
— Reporter (uncredited)
Norman Stevans
— Official (uncredited)