Aristotle Plato ("Soc") Socarides has got a business card as unusual as his name: he's a private investigator, a diver, and a fisherman operating out of Cape Cod. But he's definitely got the perfect resume when the owners of a marine park desperately need someone to prove that a suspect is innocent of murder-the suspect being Rocky, a ten-ton killer whale who's the park's star attraction. Soc goes undercover as an employee at the Oceanus Aquatic Park, which has been closed to the public since the death of animal trainer Eddy Byron. Picketed by animal rights groups and beset by sensationalist publicity, Oceanus no longer looks so attractive to the Japanese conglomerate that's been eager to buy it. Soc's employer's, the owners of the park, want him to quickly clear the whale of suspicion, get to the bottom of why Eddy Byron died, and help convince the Japanese to close the deal. Easier said than done. Eddy Byron turns out to have been an unpleasant fellow, a heavy drinker who used outdated and cruel methods to train his animals. When another former employee dies hours before a scheduled meeting with Soc, it becomes evident that if Rocky's the killer, he's got a two-legged assistant on land. With a beautiful dolphin trainer assisting him in the water and out, Soc learns a few lessons-some quite painful-about the creatures of the sea and the people who care for them.