Marshall Thompson
Major Jeff Cummings
Kynaston Reeves
Prof. R. E. Walgate
Kim Parker
Barbara Griselle
Stanley Maxted
Col. Butler
Terry Kilburn
Capt. Al Chester
James Dyrenforth
Mayor Hawkins
Robert MacKenzie
Const. Howard Gibbons
Michael Balfour
Sgt. Kasper
E. Kerrigan Prescott
Atomic Engineer
Sheldon Allan
Sentry (uncredited)
Alexander Archdale
Minister (uncredited)
Eddie Boyce
Jacques Griselle (uncredited)
Victor Hagan
Villager (uncredited)
Victor Harrington
Villager (uncredited)
Jack Hetherington
Sergeant in Office (uncredited)
Richard Neller
Townsman (uncredited)
Tom Watson
Technical Sergeant (uncredited)