Sea Hunt (1958)

A jet plane suddenly goes out of control, plunging to the bottom of the sea. When ex-Navy frogman, Mike Nelson dives to locate the wreck, he's amazed to find the pilot still alive, imprisoned in the watertight cockpit. Mike estimates there's less than fifteen minutes of life-giving oxygen left. And he knows that if he opens the canopy, the ocean's pressure will crush the pilot.

An explosion rocks a Wyoming coal mine, flooding the shafts and costing the lives of 30 miners. Mike Nelson dives to locate the cause of the disaster. Deep in the shafts, Mike discovers two survivors trapped in an air pocket. It looks like Mike can only get one of them out, leaving the other to perish.

When deep sea divers go too deep or stay down too long, they suffer from an excess of nitrogen in the bloodstream. The resulting narcotic effect is called "Rapture of the Deep." When a party of skin divers falls victim to the "rapture," one of them becomes homicidal.

Before Mike Nelson can investigate the disappearance of two geologists the sea washes one of them upon the beach, his body bearing marks apparently made by the suction valves of a giant octopus. When later the body of a young boy is found with the same mysterious marks, Mike is sure that the killer is a diabolically clever man who has somehow found a way to duplicate the mark of an octopus.

Mike Nelson rescues an unidentified girl from drowning. The Immigration Department suspects she's an illegal alien. Released in Mike's custody, the girl confesses she was towed into the country underwater in a sea sled operated by a ring of border-runners.

Lovely Kay Dalton, terrified of the sea, persists in skin-diving. Object: recover a cache of stolen diamonds on the ocean floor. Although Mike Nelson warns that she will never conquer her fears, Kay refuses to be deterred.

A pretty magazine photographer employs Mike Nelson to help her film a sunken barge off the coast of Mexico. Despite Mike's warnings, she gets trapped on the bottom of the sea.

Hired to test a new electronic fish finder, Mike Nelson cruises to a small Mexican fishing village where he finds a strange phenomena - every fish in the vicinity seems to have disappeared. Mike uses the latest scientific "miracles" to pierce the mystery of the disappearing fish and save a fisherman's life - and the life of the entire village.

When two ruthless treasure hunters dupe a young skin diver to help them loot a long-sunken ship, underwater investigator Mike Nelson foresees disaster. Mike braves the wrath of man and sea to save the lad from tragedy.

Mike Nelson and pretty Cathy Morton, U.S. Government undercover agent, search for a missing nose cone on the floor of the Caribbean. Unseen, three armed and dangerous foreign agents follow the expedition determined to capture the cone for their own government. Mike finds the vital missile part and risks his life to deliver it to Naval Intelligence.

A savage killer whale blockades a strip of coastline, capsizing boats and harassing skin divers and swimmers. Mike Nelson, armed with a shark-harpoon gun, engages the killer in a wild and desperate undersea battle.

A Red scientist defects to the West and comes to the U.S. Kidnapped by Communist agents, he is soon aboard a Pacific liner enroute to Moscow and a doubtful future. Undersea criminologist Mike Nelson drives a midget submarine through the shark-infested Pacific and storms the heavily-guarded liner.

During a shark-filming expedition, Brent Marshall's flirtatious wife pays him no attention, concentrating instead on Mike Nelson and two cameramen. Enraged with jealousy, Marshall severs a camera cage cable and drops his three supposed "rivals" into shark-filled waters. Mike escapes the underwater prison and attempts to rescue the trapped cameramen.

A Smithsonian Institute professor employs Mike Nelson to salvage a German submarine sunk off the coast of South America. But two "hard-hat" divers in conventional diving helmets and lead boots are after the same prize. Mike defies his competitors - and an entire government - to salvage the sub and fill a missing page in the history books.

Lewis Hale tells Mike that he has invented a miraculous machine which locates sunken ships laden with gold. Mike discovers the machine is actually a stolen Top Secret U.S. Navy device, and pitches into a life-or-death struggle with Hale to retrieve it.

On underwater "safari" in Florida's dense swamplands, Mike is suddenly gripped by a massive electric current and nearly loses his life. Recovering, he learns that a poacher is using electric shock to kill all the fish in the area. Mike and a Seminole Indian guide join forces with the State Fish and Game Commission to capture the "Electrocuter."

A girl is placed in a straight jacket, securely locked in a trunk and cast to the bottom of the sea. It's all part of a carnival act - except she doesn't come up! Mike Nelson learns the secret of the act in time to save the girl from drowning.

Mike Nelson interrupts an underwater survey in the Gulf of Mexico to save a diver whose air line is snarled on jagged rocks. This rescue plunges Mike into life-or-death clashes with man and underwater beast.

Mike Nelson accepts a job to supervise a diamond diving expedition in South America, but soon rebels when he learns his employers are poaching on somebody else's property. Mike discovers his life is in jeopardy, and uses his knowledge of sharks to capture his would-be murderers.

Caesar, a vicious alligator, escapes from a wild animal show in Silver Springs, Florida, and takes refuge in the lake in a public park. Mike Nelson volunteers to match brain and brawn with the man eater.

Gathering museum specimens in the coastal waters off lower California, Mike Nelson learns of a derelict mine which has drifted into the harbor of a nearby town. The town's principal industry - a nitrate factory - will blow up and destroy the city if the mine explodes. Mike works with local fishermen to locate the drifting "killer" before it costs hundreds of lives.

Playboy sportsman Elliot Conway and his wife Gloria employ Mike Nelson to teach them skin-diving and guide their underwater "safari" for sharks in the waters off Peru. Mike fights a school of hungry sea beasts to save the lives of his "pupils."

When the State of Florida is plagued with a series of underwater crimes Mike Nelson is called to organize and train an underwater police force. Learning that a thief has just looted a cabin cruiser and escaped underwater, Mike gives his pupils a "practical" lesson. Mike uses his vast knowledge of the sea to trap the thief.

Despite warnings from his friends, Mike Nelson dives to investigate an underwater grotto where - according to legend - a beautiful mermaid lures men to destruction. Mike fights for his life against the "mermaid."