When Primus develops a sophisticated robot to complete a risky underwater operation, little does he realize that George Benton has other plans for the robot-namely to recover Russian art treasures from a sunken liner.
Nicola, a photographic model, and a woman's-lib advocate is determined to attempt a dangerous dive. Nicola steals an untested underwater breathing device that has been altered and is lethal if used.
While investigating the disappearance of all fish life off the island of Mangaya, Primus becomes involved with the kidnapping of Freemont, an American Ambassador.
An electrical storm causes an explosion and fire on an offshore oil-drilling platform. Carter Primus must rescue a colleague who is trapped in the raging inferno.
Drama involving an impending hurricane. While training dry land miners to dig on the ocean Primus discovers that two miners searching for ore samples are missing.
Toni and Charlie are trapped in a shark cage which drops to depths beyond which divers should go and Primus attempts their rescue amid a school of frenzied sharks.
Primus captures three college students while stealing his portable sub the Shark Hunter. But the students hide a more serious purpose in mind: to lock themselves to the waste pipe of a nearby chemical plant.
Primus is dogged by a sniper while he helps a community whose important economic resource, a phosphate plant, is also its greatest liability, the deadliest cause of pollution, killing all fish in the town's river.
A plane crashes into the ocean with a payload of $7,000,000 worth of industrial diamonds. Insurance investigator Derek Simpson commissions Carter Primus to locate the wreckage.
Primus is commissioned to guard a museum filled with priceless treasures. The museum is located near the sea and while Primus and his assistant attempt to install infrared devices underwater, they are trapped by a steel net.
The police chase a gang involved in the plutonium black market. Primus replaces one of the gang members, a Navy diver, after the guy is washed away dead on the beach.
Carter Primus hires professional skin divers to locate a boat which disappeared mysteriously. A whirlpool sucks them into an underwater cave. Searching for the divers, Primus and Toni Hayden fall into the whirlpool.
While Primus and Toni train three divers, one receives a gash from the sunken wreckage they're exploring and a school of 200 sharks is attracted by the blood.
