Mike and his diving team are attacked by a violent new breed of octopus. ...

Mike attempts to rescue a kidnapped friend. ...

While on a research project, Mike encounters saboteur frogmen attempting to destroy the Panama Canal. ...

Mike Nelson and three of his students search for a missing diver, who was dragged deep below the surface by a large fish that he speared. ...

To fund research for an ocean plants into food products project, Nelson agrees to travel to Puerto Blanco/South America. There he teaches skin diving to a thrill seeking ...

A professor and his daughter hire Mike to harvest a rare underwater plant from a South American lake. The anxious old man joins Mike for the dive, comes up too quickly, a ...

Mike Nelson travels from his home base of Marineland, California to Silver Springs, Florida. There he trains a pair of Florida Highway Patrolmen in scuba diving so as to ...

Mike Nelson goes after a vicious alligator that escapes from a wild-animal show in Silver Springs, Fla. and takes refuge in the lake in a public park. ...

Mike dives to see how a woman escapes from a locked truck at the bottom of a lake. Watching a near-tragedy underwater, he takes his concerns to Harry Baldwin, the head of ...

Mike hunts down a killer whale that has been terrorizing a local coastal community. ...