Another movie company using Mike as an advisor needs his help when a planned torpedo blast traps the star and a Hollywood columnist onboard a sinking ship.

While helping to test a friend's underwater radio device, Mike discovers a submerged radio beacon, camouflaged and guarded by an electric gun.

Mike leads the way in a salvage operation to recover more than a million dollars' worth of gems from the captain's safe of a sunken ship.

Mike responds to a ""man overboard"" situation, but an extensive search turns up no victim.

A scientific society hires Mike to obtain fossil samples from a newly-discovered underwater cavern for the purpose of authentication.

In preparation for the visit of a foreign head of state, Mike helps the Coast Guard do a security check on the area.

A new revolutionary leader asks Mike to help him retrieve his country's hidden gold reserves, believed to have been hidden aboard a scuttled freighter by the ousted former dictator.

Mike becomes suspicious when his hired dive on a Spanish galleon yields a rare art treasure.

Mike tries to outmaneuver a foreign harbormaster as he attempts to retrieve a diplomatic pouch from an airliner that crashed into the sea.

Mike attempts to deal a blow to organized crime by using a periscope camera to photograph a secret meeting of mob bosses at a lakeside estate.

Mike searches for a vanished oceanographer by retracing her charted course.

Mike, working with a pretty Secret Service agent, poses as a scientist in order to retrieve a cache of counterfeit currency from a crashed Nazi plane off the coast of a Caribbean republic.

Mike faces arrows and an alligator in the Mayan jungle while searching for a drug that could be a boon to medicine or a dangerous narcotic.

Mike tries to reach a little girl trapped in the air shaft of a mine located at the edge of a man-made lake, but the potential for a landslide hampers his attempt.

Mike discovers the wreck of a navy ship that disappeared mysteriously, and is joined by a pair of its former crew members when he dives to examine it.

An East Indian oceanographer vanishes during a series of underwater experiments with infra-red light.

Mike and an old war buddy use a new, untested ""re-breather"" to investigate an underwater missile site being constructed in the channel of a privately-owned island.

A small Latin American country calls upon Mike to help defuse a sunken munitions ship set to blow by saboteurs.

Mike and a female health official try to remove a dangerously radioactive capsule from a sunken ship.

While on patrol with the Coast Guard Auxiliary, Mike discovers a deported crime boss trying to re-enter the country, then has to rescue him from some old enemies.

Mike helps a friend in the military with his tests of underwater radar equipment.

Mike finds that someone has tapped the underwater cable used in monitoring a televised missile test.

Scientists risk triggering a tidal wave when they ignore Mike's warnings about the strength of the explosive charges they're using.

Mike straightens out a pair of teenagers who poisoned a shark Mike had captured for Marineland.

Mike goes after a newlywed teenager turned fugitive after a bungled holdup prompts him to hide in the city's storm drain system.