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