Screwball romance and homage to Jules Verne as an unlikely couple tangle with a demented billionaire's secret weapon. Garrison (Buried at Sea, Feb. 2002, etc.) has so admirably established himself as craftsman of sailing adventure that there's an urge to skip the plot details and get to the fun stuff: the delightfully dangerous drama of flawed but intrepid loners finding new strengths on the open sea as they beat the bad guys every time.
Our intrepid loner this time is David Hope, former journalist who runs scuba charters out of the Virgin Islands. Just as he scatters the ashes of his former lover, his boat is nearly destroyed by a US Navy submarine whose commander thinks Hope might have something to do with a computer shutdown that near nearly sank the sub. After the sub lets him go, Hope returns to Tortula to find that the last charter of the season has canceled. The screwball antics set in when he fails to pick up Sally Moffit, an undersea nature filmmaker, at a bar, and even so ends up helping her (she's has just been dumped by her filmmaker husband) steal some of her husband's equipment, then agrees to take her to Bermuda to film the mating habits of a species of dolphin.
Before romance can bloom, the two see a dolphin with the size and lethal abilities of a killer whale. Before they can learn more about it, they're hailed by William Tree, unctuous, effusively polite, repulsively fat offshore oil mogul who lives aboard an enormous sailing ship. It gives nothing away to say that Tree, dolphin, and computer failure are linked, that Tree is more of a Dr. Frankenstein than a Captain Nemo, and that he'll use Hope and Moffit as target for a nasty new weapon.
Skip the high-tech antics and Tracy/Hepburn banter: when it comes to high-seas action, Garrison is at the crest of the wave.