S1 • E1
Racing against time, Mike Nelson attempts a risky rescue of a test pilot trapped in his plane's cockpit 60 feet below the ocean's surface.
S1 • E2
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?
S1 • E3
While testing the skills of two divers, Mike is attacked by one of them, whom is suffering from rapture of the deep.
S1 • E4
Mike is asked to investigate when two underwater geologists disappear, one of whom washes up on the beach with marks of a struggle with a gigantic octopus.
S1 • E5
Mike Nelson rescues an unidentified girl from drowning. The Immigration Department suspects she's an illegal alien and releases her in Mike's custody.
S1 • E6
Although Kay Dalton is terrified of the sea, she is determined to dive for a cache of stolen diamonds.
S1 • E7
An old flame comes back into Mike's life, and she's nothing but trouble.
S1 • E8
Mike has been hired to test a machine dubbed "the fish-finder" on an experimental boat called The Sonar Queen, in hopes of determining why all of the fish have disappeared from the coast of a Mexican fishing village.
S1 • E9
Mike comes to the aid of a young friend, whom has been fooled into working for a couple unsavory treasure hunters.
S1 • E10
Mike searches the ocean bottom for a gone-astray nose cone.
S1 • E11
Mike hunts down a killer whale that has been terrorizing a local coastal community.
S1 • E12
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.
S1 • E13
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.
S1 • E14
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.
S1 • E15
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.
S1 • E16
Mike assists the authorities in trying to apprehend a poacher operating in the swamps of Silver Springs, Florida.
S1 • E17
Mike has serious concerns regarding a dangerous, underwater, carnival magic act.
S1 • E18
Mike comes to the aid of a young diver - in more ways than one.
S1 • E19
Mike Nelson accepts a job to supervise a diving expedition for diamonds in South America, but soon rebels against his employers.
S1 • E20
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.
S1 • E21
Mike Nelson learns of a derelict mine which has drifted into a California harbor.
S1 • E22
Mike Nelson is called in by the Florida State Police to help solve a series of underwater crimes.
S1 • E23
Mike investigates the legend of a mermaid located in an underwater cave off the west coast of Florida.
S1 • E24
A professor and his daughter hire Mike Nelson to help them search for a rare underwater plant in Costa Rica.
S1 • E25
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.
S1 • E26
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.
S1 • E27
Mike discovers a kidnapped scientist being held in an underwater prison cell.
S1 • E28
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.
S1 • E29
Mike attempts to rescue a kidnapped Latin American diplomat being held with his wife at sea on his pleasure boat named Santa Rosa.
S1 • E30
An unexpected storm capsizes a boat.
S1 • E31
A stuntman tries to break the world's skin-diving record.
S1 • E32
Hoodlums attack Mike after he explores the waters around a pier.
S1 • E33
Mike tries to prove that a woman's drowning was not accidental.
S1 • E34
Mike is hired to make a molehill out of an underwater mountain.
S1 • E35
While underwater, a member of Mike's supervised diving party goes missing.
S1 • E36
Mike's life is targeted for murder during his insurance investigation of a sunken ship.
S1 • E37
Mike investigates reports of a sea monster, which is literally causing whales to leap into the air above the ocean's surface.
S1 • E38
Mike searches for the divers who are tapping top secret telephone communications along an underwater cable.
S1 • E39
Mike battles rough weather, sharks, bullets, and even a giant clam, as he searches for a deep-water manganese deposit, which could be invaluable to the U.S. Government.
Mike Nelson
Dr. Max Schiller
Guard
Ruth Morgan
Paul Garrick
Dick Talbot
John Benton
Indio Ramirez
Thug
Police Chief Coleman