Sea Hunt

After Mike turns down an offer to work with a pair of men who run a deep sea salvage company because of their past, Mike's assistant on his current job agrees to work for them. Mike joins the three men on a treasure hunt for gold, as Mike wants to keep his former young assistant safe from harm.

While on job field testing a new device called a "Dual Sweep Transducer," common name fish-finder, Mike crosses path with a Mexican fishing village without fish, except for one man. Using the ship ("Sonar Queen") equipment, Mike finds the fish and then goes into sale mode to save the fisherman and sell the community on new technology.

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.

A mining company flies Mike 1,500 miles inland to survey a collapsed and partly flooded mine. They're trying to decide the best way to reopen the mine. During his first dive, Mike hears noises that lead him to an air pocket where two men barely are surviving. One of the miners feels there is only enough air left in the cave for 10, maybe 20 minutes. Mike has only enough air to take one of the miners out. Who will go with Mike? Who stays and hopes (with only one miner breathing the air) he'll be able to survive until Mike returns? How will they decide who lives and who risks death?