The inhabitants of Ganymede need to find mates from another world or they will become extinct. They soon discover a suitable breeding stock amongst the females of planet Earth.
Dr. Jack Costain
Ann Barlow
Detective Supt. Hartley
Dr. Morley
The Major
Cmdr. Savage
Det. Tom Grant
Joyce Malone
Medra
Thorburn
The Sergeant
Pvt. Higgins
Pvt. Jones
Madge Lilburn
Reg Lilburn
Col. Davy
2nd R / T soldier
Police Commissioner's secretary
First R/T Soldier
Lieutenant
TV Newscaster
