Season 4

E1. Point of No Return

Jan 7, 1961

Mike is trapped in a ""scubasphere"" when the cable attached to it snaps.

E2. River Treasure

Jan 14, 1961

While surveying a remote river in the South American jungle, Mike is threatened by the jealousy of a man prospecting for emeralds with his wife.

E3. The Destroyers

Jan 21, 1961

Mike investigates the source of a radar jamming signal that caused two ships to collide.

E4. Vital Error

Jan 28, 1961

A famous newsman, convinced that he has a fatal illness, tries to end his life in such a way that his wife can collect his insurance, with Mike as a witness.

E5. The Dancer

Feb 4, 1961

A scuba diving ballerina faces the possibility of underwater amputation when she catches her foot between the buckled plates of a sunken freighter.

E6. Sperling of Lamatsue

Feb 11, 1961

After being accidentally caught in a fishing net, Mike challenges an Asiatic warlord by trying to retrieve a cache of medical supplies that the dictator has dumped into a river.

E7. Rescue

Feb 18, 1961

Unaware that two of his treasure-hunting friends are trapped inside, Mike sets charges to blow up a sunken ship that is a menace to a busy shipping lane.

E8. Mercy Trip

Feb 25, 1961

Mike scouts a path through mine-infested waters so that medical supplies can reach a China Sea port hit by a cholera epidemic.

E9. Hot Tracer

Mar 4, 1961

Mike's efforts to retrieve a pair of radioactive cylinders are complicated by the presence of a headstrong youth to whom he's been giving diving lessons.

E10. Sonar Story

Mar 11, 1961

Mike uses sonar to foil a gang of underwater heroin smugglers.

E11. Amigo

Mar 18, 1961

A young Mexican boy helps Mike locate a safe entrance to an underwater fossil cave.

E12. The Aquanettes

Mar 25, 1961

Mike faces sharks and other unexpected difficulties while working with three pretty women undergoing astronaut training.

E13. Survival Kit

Apr 1, 1961

Mike is hired by a local German consul to salvage a survival kit from the wreckage of a Nazi warplane in the Caribbean.

E14. Expedition

Apr 8, 1961

While helping his former history professor search for pirate treasure off the North Carolina coast, Mike finds evidence that the underwater cave said to house the treasure has been tampered with.

E15. Bionics

Apr 15, 1961

Mike convinces a reluctant daughter to continue her father's work after he is killed testing an underwater electrical detection device.

E16. The Defector

Apr 22, 1961

A man bribes Mike to continue giving lessons to an inept diving student whom he's stopped teaching.

E17. Niko

Apr 29, 1961

Mike heads a three-man team in an effort to disarm a pair of unexploded torpedoes at the bototm of a West Coast harbor.

E18. Cougar

May 6, 1961

A restless youth and a college girl complicate Mike's attempts at capturing a poisonous lionfish.

E19. Sub Hatch

May 13, 1961

A heroic test pilot from the Korean War has his mettle tested when he must spend 24 hours with Mike in a makeshift decompression chamber after a dive to prevent the bends from killing him.

E20. The Octopus Story

May 20, 1961

Markings on the body of a dead diver convince a marine biologist that a tropical lagoon is inhabited by a killer octopus.

E21. Quicksand

May 27, 1961

One salvage diver disappears while diving on a sunken yacht off the coast of Yucatan, and Mike tries to see that two others don't share his fate.

E22. Lost Island

Jun 3, 1961

Mike teams up with a Mexican prison escapee to uncover nefarious activity on an uncharted Pacific atoll off the coast of South America.

E23. Baby

Jun 10, 1961

Mike must get past Jivaro Indians who are blocking his passage downriver as he attempts to get a young missionary's baby to a hospital for medical attention.

E24. Confidential Mission

Jun 17, 1961

Mike poses as a tourist on vacation as he tries to locate a hidden underwater missile launcher in the Caribbean.

E25. Underwater Pirates

Jun 24, 1961

Pirates try to snatch a sunken freighter away from Mike before he can salvage it for an old Navy buddy.

E26. The Meet

Jul 1, 1961

While working for the U.S. Treasury to break a counterfeiting ring, Mike intercedes in a kidnapping.

E27. Dark Evil

Jul 8, 1961

A pretty woman and her father, vacationing in the Bahamas, become killers after inadvertently eating a variety of fish that causes hallucinations.

E28. Sunken Car

Jul 15, 1961

A sunken truck points Mike to the murder of a political boss, and the killer is the father of a good friend of Mike's.

E29. Hit and Run

Jul 22, 1961

Mike goes after an egocentric movie star who injured a friend of Mike's in a hit-and-fun speedboat accident.

E30. The Saint Story

Jul 29, 1961

While searching a Latin American harbor for a sunken statue, Mike discovers a UHF homing beacon being used to guide submarines into the port.