In 1930s Florida, Nia visits her snobby cousin Bernice, who has been displaced from high society to live with her new step-father on a tiny island off Tampa. After witnessing Bernice’s murder of the step-father (possibly because of his sexual abuse), Nia flees her cousin and both end up in the ocean, where Bernice drowns and is transformed by an ancient water goddess into a super-powered servant in a plot to awaken the Leviathan, the primordial father of all the elemental gods, whose long slumber has allowed mankind to rise to supposed dominion over the world. Nia is saved from death by a mysterious elemental with dominion over decay, and spends the next four years as a human statue/cocoon before she hatches into a servant of the earth and must stop Bernice and the water goddess from destroying the human race.Packed with accurate details about Florida in the Thirties; a hideous water-worshipping cult reminiscent of Lovecraft’s Innsmouth; José, a 19th century Spanish pirate serving as Bernice’s mentor; and a bumbling fire insurance agent, Fathom passes back and forth from dark fantasy to atmospheric horror in a gory and suspenseful ride. Told from the viewpoints of teenage Nia, and adults Sam and José, this book works more as dark fantasy a la Gaiman’s American Gods than horror, revealing too much of the unknown plot elements through José’s story and breaking the tension created by Sam and Nia’s narrations. However, the horror element works well when the latter two are telling the tale, and the final chapters build up a nicely tense scene of crisis and desperation as Nia and her companions race to prevent the wakening of the terrible world-destroyer Leviathan. The non-stop action, youthful protagonists, and “old gods” plot will appeal to many teens and both fans of Gaiman and H.P. Lovecraft. Extreme graphic violence and moderate profanity, mentions of sexual abuse. Ages 14+