Mike discovers an important manganese deposit, but an ambitious young geologist, sharks, and an approaching hurricane threaten to silence him before he can inform the government.
The murder of a telephone company employee leads Mike to an underwater cable that is being tapped to access top-secret research conferences.
Mike investigates reports of a sea monster off the coast of Mexico.
Mike is hired by an insurance company to investigate the sinking of a freighter, but a murder indicates that someone doesn't want him to complete his task.
A group of sportsmen hire Mike to supervise their skin-diving outing, whereupon one of them sneaks off and begins photographing secret Navy facilities.
Mike is hired to destroy an underwater offshore peak that is notorious for ripping the hulls out of passing ships.
An underwater camera holds the key to determining whether a woman's drowning was accidental, as her husband claims, or not.
After locating a leak in a gas line and retrieving a young boy's sunken bicycle, Mike is beaten up and threatened by a gang of thugs.
Mike's work on a movie prompts a fellow stunt diver to attempt a dangerous record-setting dive.
Mike and three other survivors share a life raft after a storm capsizes their boats.
Mike leads a diving team in rescuing a Latin American diplomat and his family from kidnappers.
A frustrated former athlete pushes his children to be Olympic swimmers, resulting in their becoming trapped in a cave by a rising tide.
Mike finds a famous rocket scientist being held in an underwater prison by enemy agents.
Mike is hired by a playboy sportsman to supervise their underwater shark "safari" in the waters off Peru.
A pair of prospectors hire Mike to trace the source of radioactive fish with a Geiger counter in hopes of finding a uranium deposit.
A professor and his daughter hire Mike to help them search for a rare underwater plant in Costa Rica.