To fend off bankruptcy, the owners of an Indian Ocean shipping company have started taking on passengers as well as freight; so Sunglow, an old diesel-engined vessel skippered by Capt. Shamus Cassidy, sets out from Mombasa with about a dozen passengers who've signed on for a ""Capricorn Adventure Cruise"" around the small islands on the coaster's route. Among these supposed vacationers, however, there's a familiar assortment of ulterior-motive types: Beryl Clutterbutt is searching for lost gold, equipped with an old chart drawn by her shipwrecked great-grandfather; ornithologist Stephen Blake is a cop incognito; one of the others--a minister, a cockney, a beautiful divorcee--is a fugitive from justice. Furthermore, the ship's nasty second-in-command has been bribed (by the shipping-company heir) to arrange for Sunglow's irreparable damage: an insurance scare! So there's no shortage of adventure--or Love Boat-ish subplotting--ahead as Sunglow makes its leisurely way from atoll to atoll. Nature provides a near-disastrous cyclone. Surviving crewmen from a wrecked freighter--a surly, ungrateful bunch--add to the tensions. One of the stops turns up unexpected danger--when they stumble on the top-secret construction of what might be a Soviet missile site!! And, though Mrs. Clutterbutt's chart leads to a skeleton instead of gold, her teenaged nephew Jim gets a chance to assert himself for the first time--while lusting hopelessly after that beautiful divorcee. Busy, busy--and more than a little silly, silly--but fans of ship-to-shore action will find this only slightly less satisfying than Trew's many previous nautical-suspense excursions.