Mike happens upon a jealous couple prospecting for emeralds while surveying a remote river in South America.
A newspaperman becomes convinced that he's dying from a fatal illness and tries to end his life in such a way that his wife can collect his insurance.
Mike must retrieve a cache of medical supplies that were dumped in a river before a local witch doctor can get his hands on them.
Mike is assigned to chart a path through mine-infested waters so that medical supplies can reach a port city suffering from an epidemic of cholera.
Mike goes up against underwater heroin smugglers and uses sonar to foil their scheme.
A German consulate hires Mike to salvage a survival kit from the wreckage of a World War II U-Boat.
Mike helps his former college history professor search for buried pirate treasure off the North Carolina coast.
After a man is killed testing an underwater device, Mike convinces his hesitant daughter to continue her father's work.
An man offers to pay Mike extra to continue teaching diving lessons to an inept student.
A test pilot must spend 24 hours in a decompression chamber after a dive in order to keep the bends from killing him.
Markings on the body of a dead diver convince a marine biologist that a killer octopus inhabits a lagoon. Mike must prove or disprove the theory.
Mike tries to make sure two salvage divers don't disappear while diving on a sunken boat off the coast of Yucatan. It seems as though a previous diver vanished completely.
Mike and an escaped Mexican convict uncover nefarious activity on an atoll off the South American coast.
Hostile natives interfere with Mike's passage downriver when he attempts to get a missionary's baby to a hospital for medical attention.
Mike goes undercover once again, this time as a tourist, in order to locate an underwater missile launcher in the Caribbean.
Mike is hired by an old Navy buddy to salvage a sunken freighter but pirates are out to make sure they get there first.
Mike gets involved in counterfeiting and kidnapping when he's hired to work for the Treasury Department.
After a friend of his is seriously injured in a speedboat accident, Mike goes after the movie star responsible.
Mike must get insulin to a diabetic whose boat has been sunk by his wife, unaware of his condition.
In South America, Mike's assistant is trapped underwater by an overturned truck containing drums of poison that could endanger the water supply of a port city.
Someone is sabotaging a series of experiments that Mike is conducting for the Coast Guard.
Mike must disarm a torpedo that's been sent into the outflow tank of a hydroelectric plant.