Undersea diver Mike Nelson is a former navy frogman who now works at Marineland. When an experimental supersonic fighter is forced to ditch at sea, the manufacturers hire Mike to locate it and attach a marker buoy so it can be raised. Mike has little trouble finding the aircraft in about 60 ft. of water. What he also finds is the pilot, alive in the airtight cockpit, but with only 15 minutes of oxygen remaining in his tanks. It up to Mike to find a way to get him out. Written by garykmcd

Mike travels 1500 miles inland to a flooded mine where two men are trapped in a foul air pocket. He reaches them, but his dilemma is that there is only enough air in his tank to rescue the miners one-at-a-time and not enough air in the pocket for the remaining man to survive until he returns with more air. Who will go? Who will stay? How will he decide? Written by jimmie d

Mike Nelson is hired by a mining company that has located a source of beryllium in an underwater location off the coast of Madagascar. The site is 170 ft. below the surface and Mike points that not only do you require experienced divers at that depth but anyone diving below 120 ft. is subject to nitrogen narcosis, also known as rapture of the deep, where men begin to hallucinate. Mike's job is to find divers who can work at that depth but for two divers who know each other, their personal animosity may get in the way. Written by garykmcd

Mike Nelson is hired to locate two geologists who were conducting a survey just off the coast. When a body washes up on shore, it turns out to be one of the missing men. The tentacles marks on his leg seem to suggest that he was attacked by an octopus but Mike doesn't believe that as an octopus will not normally attack swimmers. Unbeknown to him the second diver, Wilkes, wants to keep the survey results for himself as it indicates the existence of large oil deposits. Wilkes also has a partner and as a result Mike's life is in danger. Written by garykmcd

The Immigration Department contacts Mike after he rescues a young woman from the ocean. Officials believe she is involved in smuggling foreign criminals into the states. After having her released into his custody, the tables are turned and Mike finds himself being held by the woman and her brother. They want to keep Nelson quiet until their other brother has safely slipped into the country. Written by Jay Phelps [email protected]

A mysterious woman who's hired Mike for private diving lessons proves so inept that, after a week, Mike drops her fearing she'll accidentally kill herself. Her motivation for the lessons becomes clear when an insurance investigator shows up; her boyfriend is doing time for a jewel heist and the loot is stashed 150 feet down. Written by Jay Phelps [email protected]

While working on a project to formulate a safety code for skin divers, Mike meets up with an old flame who has her own safety issues while skin diving. She is trying to combine skin diving with her job as a photographer, but needs a portfolio and wants Mike's help in shooting a sunken barge off the coast of Mexico. Her impatience brings both Mike and her to the brink of death. Written by Jay Phelps [email protected]

Mike Nelson has been hired to test a new relatively inexpensive sonar device that can be used as a fish finder. After a day of testing they dock in a small Mexican village where an old fisherman is being beaten. It seems the old man is catching plenty of fish while the other fisherman are returning practically empty handed. He's refusing to tell them where this fishing spot is located and some are accusing him of witchcraft. Mike steps in not only to protect the old man but to find out why the fish seem to be congregating in one particular location. Written by garykmcd

Salvage operators want to hire Mike to help them find the wreck of a Japanese freighter that went down off the coast of Mexico in the 1920s. The ship is supposed to have $100,000 in gold in the safe in the captain's office and they need an experienced diver offering Mike $20,000 to retrieve it for them. Their reputation precedes them however and Mike turns them down flat. When a young friend takes the job, Mike has no choice to go with him but keeps his eyes open knowing that at some point the salvage men will try to kill them. Written by garykmcd

Mike is hired by the US government to locate the nose cone of an experimental rocket that went down in the Caribbean. It's a hush-hush operation and Mike is joined by another agent, Catherine Martin, an expert diver who also happens to teach judo. As they go out to sea, they are being followed. Mike and Catherine have little difficulty locating the nose cone but when Mike gets trapped under water and Catherine taken prisoner by the enemy agents, both of their lives are on the line. Written by garykmcd

Mike hunts down a killer whale that has been terrorizing a local coastal community.

Mike pilots a mini-submarine in an attempt to rescue a Russian scientist defector from a ship, where he is being held by his Soviet kidnappers.

Nelson is hired to study shark behavior at various depths and the effects of a new shark repellent.In Caribbean waters and with two other divers assisting him,he is lowered in a shark cage to accomplish the assignment.Before it is all over Mike is reminded that human beings also pose a danger to his life. Written by dubchi

Nelson,brought to the Latin American port of Santa Pueblo,investigates a recently found German WWII submarine.The sub,which had been on a secret mission,may contain secret documents or weapons,the remains of top Nazi Party members-or gold! Hard hat divers backed by the country's dictator interfere in the exploration. Written by dubchi

An overly energetic man appears on Nelson's boat and claims to have built a machine which can find shipwrecks by calculating where the shifting of the earth's plates have moved them. After a successful test run, the objective is to find lost barges carrying gold! Oddly, Nelson is more interested in the machine itself. Written by dubchi

Mike assists the authorities in trying to apprehend a poacher operating in the swamps of Silver Springs, Florida.

Mike dives to see how a woman escapes from a locked truck at the bottom of a lake. Watching a near-tragedy underwater, he takes his concerns to Harry Baldwin, the head of the carnival show. The girl's life is placed in serious danger when Harry sabotages the trick in revenge for her falling in love with another man. Written by Jay Phelps [email protected]

Mike comes to the aid of a young diver - in more ways than one.

Nelson,in Florida and in the early stages of testing an underwater listening device (a Hydraphone),sidetracks to Panama to train scuba diving to two geologists.The geologists are seeking to find diamonds in a Panamanian riverbed.Snake infested waters and the Hydraphone eventually save Nelson from his students. Written by dubchi

Mike Nelson goes after a vicious alligator that escapes from a wild-animal show in Silver Springs, Fla. and takes refuge in the lake in a public park.

Mike Nelson learns of a derelict mine which has drifted into a California harbor.

Mike Nelson travels from his home base of Marineland, California to Silver Springs, Florida. There he trains a pair of Florida Highway Patrolmen in scuba diving so as to combat crimes, such as outboard motor thefts. However, a robber well versed in scuba diving becomes the FHP's first test in underwater policing. Written by dubchi

Diving for sponges off of Florida, Mike hears bells as a fierce current tries to force him into a cave. He barely escapes death, but learns many other divers have met their demise after being lured in by an evil mermaid. Obsessed with solving the mystery, Mike is determined to dive again. Written by Jay Phelps [email protected]

A professor and his daughter hire Mike to harvest a rare underwater plant from a South American lake. The anxious old man joins Mike for the dive, comes up too quickly, and develops the bends. Hoping to save the man's life, Mike radios a nearby military base looking for a pressure suit used by high-altitude pilots. Written by Jay Phelps [email protected]

Two prospectors (one of whom is at times violently paranoid about being cheated) ask Nelson to join them in a search for uranium deposits in a river bottom. When after two futile weeks Nelson finally has a positive reading on his Geiger counter, the paranoid partner snaps and lets his suspicions get the better of him. Written by dubchi

To fund research for an ocean plants into food products project, Nelson agrees to travel to Puerto Blanco/South America. There he teaches skin diving to a thrill seeking millionaire hunter and his wife. The boorish hunter wants to kill a large shark and a giant squid for his trophy case. An accident quickly matures the man. Written by dubchi

While off the coast filming whales, Mike and his boat-mate learn another guided missile expert has disappeared in the area. Investigating suspicious activity by some divers he spots, Mike discovers the missing scientist is hidden beneath the surface in an underwater holding cell. Written by Jay Phelps [email protected]

Offshore near Santa Barbara,Nelson is testing a sea scooter. Meanwhile,a know-it-all ex-athlete and his wife are spending the day at the beach with their two kids. The kids are carelessly allowed to explore the area and end up trapped in a cave which high-tide will engulf. Nelson and his scooter attempt to be of help. Written by dubchi

Mike attempts to rescue a kidnapped Latin American diplomat being held with his wife at sea on his pleasure boat named Santa Rosa.

Mike shares his rubber life raft with three others following a sudden storm that sank their boats. It's soon clear the others have no experience on the sea, making Mike their sole hope for survival. After six days adrift, everyone's strength and hope has been depleted. Written by Jay Phelps [email protected]

Stuntman diver Tom Gale wants to make a name for himself by diving to 380 feet and setting the skin diving depth record. Mike tries to talk him out of risking his life with such a reckless grab at publicity, but gets nowhere. The young man is clearly being pressured into this by his father, a former athlete who's willing to risk his son's life for another record. Written by Jay Phelps [email protected]

After finishing up a job, Mike retrieves the bicycle of young Jimmy who lost it off the pier. For some reason, his dive has upset a gang of thugs who rough him him. Clearly, there's something on the bottom that the hooligans didn't want found. Mike comes back for a late-night dive to discover what it might be. He's lucky his new friend Jimmy is looking out for him. Written by Jay Phelps [email protected]

The police ask Mike for his thoughts on a man whose wife didn't resurface after photographing a shipwreck. The husband says she simply went deeper than she could handle. Examining the couple's photos, Mike realizes the man's lying. To get a confession, Mike fools him into believing they can retrieve her body from 500 feet down. Written by Jay Phelps [email protected]

Mike is called to Canada by an engineering firm to destroy Killer Rock, an underwater peak that has caused many ships to sink and hundreds to die. The chief engineer of the company dives with Mike and they discover a cave system they can fill with explosives. The decision is made to use highly-dangerous liquid nitro to destroy the shipping hazard. Written by Jay Phelps [email protected]

Avalon Air hires Mike for the easy job of watching over a group of competent sports divers he knows well. Joining them is one stranger, George Peterson, who goes missing from the rest of the divers. A search finally finds him on the off-limits side of San Granada island, photographing a top secret Navy facility for the underwater launching of missiles. Written by Jay Phelps [email protected]

Mike investigates a sunken freighter for an insurance company and to search for an earlier diver who never resurfaced. The salvage ship operator he hires to transport him wants the wreck all to himself. Not hesitating to kill again, he refills one of the air tanks with deadly carbon monoxide. Written by Jay Phelps [email protected]

Mike investigates reports of a sea monster, which is literally causing whales to leap into the air above the ocean's surface.

Mike investigates the murder of a diver who maintained an underwater phone cable connecting a chemical company with the mainland. He discovers the wire is being tapped to gain information on a top secret project at the chemical company. The cable is monitored for them to tap in again so Mike can capture the spies. Written by Jay Phelps [email protected]

Mike Nelson is a S.C.U.B.A. diver in the days when it was still very new. He works alone, and the plot was mostly carried through his voice-over narrations. These gave the show a flavor of a radio program. Typical adventures were finding a downed satellite or sunken treasure. Written by John Vogel [email protected]