Craig Stevens as Col. Joe Parkman

William Hopper as Dr. Nedrick 'Ned' Jackson

Alix Talton as Marge Blaine

Donald Randolph as Gen. Mark Ford

Florenz Ames as Prof. Anton Gunther

Paul Smith as Corporal

Paul Campbell as Lt. Fred Pizar

Pat Conway as Sgt. Pete Allen

Phil Harvey as Lou

Helen Jay as Mrs. Farley

Bing Russell as State Trooper

David McMahon as Capt. Frank Carver

Marvin Miller as Narrator (voice)

Michael Forest as Photographer (uncredited)

Sumner Williams as C-47 Pilot (uncredited)