Mike tries to free the pilot of a downed jet from his watertight cockpit before his air runs out, without causing the man's death from the water pressure.

While investigating the cause of a mine flood that killed thirty men, Mike stumbles upon an air pocket with two survivors.

A grudge between two divers whom Mike is testing for underwater mining skills becomes a secondary issue when one of them contracts nitrogen narcosis.

Before Mike can investigate the disappearance of a pair of skin-diving geologists, one turns up dead on the beach bearing marks resembling the suction valves of a giant octopus.

Mike helps the Immigration Department Border Patrol break up an underwater border-running operation.

A beautiful woman hires Mike to give her diving lessons for mysterious reasons.

An attractive magazine photographer hires Mike to assist her in getting pictures of a sunken barge off the coast of Mexico.

Hired to test a new electronic fish-finder, Mike encounters a village where every fish in the vicinity has disappeared.

A pair of ruthless treasure hunters dupes a young skin diver into helping them loot a sunken ship.

Mike dives into the Caribbean to recover the lost nose cone from an ICBM rocket before enemy agents can get it.

A killer whale is capsizing boats and endangering scuba divers and swimmers along a stretch of coastline.

Mike plays commando in rescuing a scientist who had defected from Soviet kidnappers who are returning him to Moscow aboard a Pacific liner.

Mike and two cameramen are imperiled when an irrationally jealous man drops their camera cage into shark-infested waters.

Mike competes with a pair of helmet divers to salvage a German submarine sunk off the coast of South America.

A man claims to have invented a machine that can locate ships carrying gold.

Mike is nearly killed by a massive electrical jolt used by a poacher to kill fish in the Florida Everglades.

Mike comes to the aid of a female escape artist when her underwater stunt goes awry.

Mike interrupts an underwater survey in the Gulf of Mexico in order to save a diver whose air line has become snarled.

Mike supervises a diamond diving expedition in South America, but discovers that his employers are poaching on someone else's property.

A vicious alligator escapes from a wild animal show and takes refuge in the lake of a public park.

The State of Florida hires Mike to organize and train an underwater police force to deal with a series of underwater crimes.

Mike investigates an underwater grotto said to feature a mermaid that lures men to their deaths.

A professor and his daughter hire Mike to help them search for a rare underwater plant in Costa Rica.

A pair of prospectors hire Mike to trace the source of radioactive fish with a Geiger counter in hopes of finding a uranium deposit.

Mike is hired by a playboy sportsman to supervise their underwater shark ""safari"" in the waters off Peru.

Mike finds a famous rocket scientist being held in an underwater prison by enemy agents.

A frustrated former athlete pushes his children to be Olympic swimmers, resulting in their becoming trapped in a cave by a rising tide.

Mike leads a diving team in rescuing a Latin American diplomat and his family from kidnappers.

Mike and three other survivors share a life raft after a storm capsizes their boats.

Mike's work on a movie prompts a fellow stunt diver to attempt a dangerous record-setting dive.

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.

An underwater camera holds the key to determining whether a woman's drowning was accidental, as her husband claims, or not.

Mike is hired to destroy an underwater offshore peak that is notorious for ripping the hulls out of passing ships.

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 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.

Mike investigates reports of a sea monster off the coast of Mexico.

The murder of a telephone company employee leads Mike to an underwater cable that is being tapped to access top-secret research Conferences.

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.