As always, Whitney, headmistress of handsomely-schooled suspense, takes her heroine from ""odd disquiet"" to a beautifully spaced trail of deadly secrets amid lush, well-researched scenery: this time orchid culture and sunken-treasure excavation fill out the contempo-gothic mystery. Laurel York's first disquiet stirs when Marcus O'Neill, a tanned stranger, drops into her Long Island bookstore--urging her to come to the Florida Keys to visit her long-estranged father, famous novelist Clifton. (Like fathers in many a Whitney tale, Cliff left Laurel's late mother for another woman.) Now, it seems, Cliff's second wife Poppy has died, leaving their two daughters, Iris and Fern. And a tiny orchid, sent by half-sister Fern, gives Laurel her first ""presentiment."" But despite the old anger at her father, and her mother's posthumous warning (""Something is terribly wrong in that house""), Laurel leaves for Florida. After a history-rich drive through the Keys, she arrives to find a withdrawn Cliff, a coolly hostile Iris, and a wispy, fey Fern. Cliff's secretary, Alida Butch, seems preoccupied and upset. Then there's that sinister photograph on the wall of Laurel's room: eyes peering through a huge orchid! And what about Poppy's bizarre death in the orchid greenhouse? Or Poppy's death-threats against wealthy, middle-aged Derek--who hunts for treasure on the ocean bottom and wants to marry Iris? Well, Laurel does a bit of diving above Derek's new find--a Spanish galleon--only to meet watery danger. Next: Alida tries suicide, while rumors about Derek proliferate. And finally, after a yacht party featuring real-life pirates, murder runs rampant. . . with Laurel nearly falling victim amongst Poppy's orchids. Reliable entertainment: Whitney in full bloom.