A marine biologist and a government agent investigate mysterious deaths and rumors of a sea monster in a secluded ocean cove, and find themselves involved with a marine biology professor conducting secretive experiments, international spies trying to steal his secrets, a radioactive light on the sea bottom, and the malevolent thing which guards it.

Cast: Kent Taylor, Cathy Downs, Michael Whalen, Rodney Bell, Phillip Pine, Vivi Janiss