Early in this disappointing suspense novel from MWA Grand Master Clark (All by Myself, Alone), 28-year-old Aline Dowling finds the body of her 18-year-old sister, Kerry, at the bottom of their parents' swimming pool at their home in Saddle River, N.J. A large wound at the base of Kerry's skull reveals that she was murdered. The immediate suspects are a brain-damaged neighbor, Jamie Chapman, and Kerry's boyfriend, Alan Crowley, with whom she had a recent fight. Then there's the unknown motorist who pulled over to help Kerry when she had a flat and proceeded to aggressively hit on her. Kerry's mother is convinced Alan is guilty, while Jamie's mother fears her son may have been involved. Homicide detective Mike Wilson teams up with Aline, recently appointed as a guidance counselor at the local high school, to investigate. Aline's attraction to two handsome suitors—Mike and lacrosse coach Scott Kimball—never generates much heat, and Jamie's confused story about the person he calls Big Guy, whom he saw hit Kerry and push her in the pool, remains a tantalizing unknown. This effort falls far short of Clark's best. Agent: Bob Barnett, Williams & Connolly. (Apr.)