This is Kemprecos' third mystery featuring Cape Cod PI Aristotle "Soc" Socarides.
Hired by an investment firm, Soc goes undercover at Oceanus, a marine theme park, to find out if killer whale Rocky did in fact slaughter its trainer, Eddy Byron. Soc's answer will help a Japanese conglomerate decide if it wants to buy Oceanus. Intrigued by the question of whether the whale, with its social tendencies, could kill humans, Soc takes the case and immediately runs up against the Sentinels of the Sea, a group picketing Oceanus, which they call a "whale jail."
Soc hopes to learn more about Rocky from the mammal's previous trainer and from the former Oceanus public relations director, who was fired for not keeping the lid on Eddy's death. When Soc discovers the PR man has been murdered, Rocky's guilt doesn't seem so likely. Steering a clear course through the murky waters of animal rights and marine parks, Soc lands firmly on the shores of entertainment.