Rex Bana is heroically struggling against the parental battles of raising their misbehaving two-year-old boy triplets, but Jesse has her own problems down at the medical examiner's office of Maui County. She's discovered an unusual string of recent accidental deaths, most of them drowning and shark-attack victims. Rex's ever-suspicious mind conjures horrors of another serial killer, but he's grown complacent, his hunting abilities dulled and rusty with disuse. He even fails to capture a mischievous and laughing thief at Sara's Garden. More victims are found, and a hotel construction site is blown up by terrorists. Something is obviously amiss on Maui. With his resources tied up catching a terrorist, Sheriff Joe Tonono enlists Rex's help in catching the murderer. At the same time, Rex is getting an education about his new Hawaiian home, its legends, and its proud heritage from the Jesse's native assistant, Dr. Ori Alika. He's particularly interested in the legend of an evil shark god named Nanaue. He also discovers the barely veiled hatred some native Hawaiians hold for the rich and arrogant tourists that are destroying their islands and the seas around them. The tourists ask ignorant questions like "Do they speak English on Maui?" or "Do they take American money?" Just as Rex and Jesse are closing in on the killer, Jesse suddenly disappears. Rex and Joe must return to the neighboring island of Moloka'i in a desperate search for Jesse. It's a dangerous chase that ends in death on the sheer cliffs above the historic leprosy colony on the Kalaupapa peninsula.