AllMovie

"They'll never get out of that," a henchman coldly states when a truck containing coast guard officer Terry Kent (Ralph Byrd) and scientist Dick Norman (Allen Connor) plunges over a cliff and into the ocean. But both miraculously survive and Terry can continue to hunt down Boroff (Bela Lugosi) and his disintegration gas, which is about to be shipped to a foreign power. With a radioactive tracking device, Terry learns the whereabouts of the ship, which is destroyed after a furious battle. Degado (George Chesebro), Boroff's chief henchman, manages to escape into the cave, however, and when he tries to follow, Terry is once again attacked by Thurg (Richard Alexander), Boroff's mute slave.