Singapore, Singapore

After meeting with Grayford, of the British Secret Service, CIA agent Flynn (the son of Errol) joins up with four Marines to search for 17 fellow soldiers reported missing. They discover that Ray, a mad scientist, is keeping the missing men alive through frozen hibernation and is preparing to perform experiments to brainwash his victims. Ray offers to turn over the Marines for cash and weapons, but his plans are foiled. Flynn and Downes, one of the Marines, sneak aboard Ray's floating laboratory and rescue the men; and the British forces, along with the three other volunteer Marines, destroy the ship.