The 11th adventure of Santa Teresa, Calif., PI Kinsey Milhone has a dark tone-due in great part to Kinsey's working this case mostly at night. Kinsey agrees to look into the 10-month-old death of Lorna Kepler, a young woman whose decomposed body was discovered in her cabin so long after death that it was impossible to determine the cause. Kinsey's client, Lorna's mother, who works the night shift in a 24-hour diner, suspects murder. So does Kinsey, especially after investigating Lorna's effects and her considerable assets, some unaccounted-for. An anonymously delivered pornographic tape adds to the emerging portrait of the dead woman as an intriguingly self-sufficient, ambitious woman of the evening. In nighttime forays, Kinsey talks to an all-night deejay whom Lorna often visited at his studio; she meets-and befriends-a prostitute who occasionally teamed up with Lorna to party with clients. She also investigates the victim's day job as a part-time receptionist for the water district, where a high-stakes development project is currently raising tempers. A host of suspects includes a porn filmmaker in San Francisco, members of Lorna's family, her landlord, the water district employees and even a smooth-dressing cop, whom Kinsey talks to at night. But lack of sleep dulls Kinsey's perceptions and it takes two more deaths and the surprise appearance of a deus ex limousine to lead her to a solution. Even sleep-deprived, Kinsey shows spunk and appeal, but she is not at her sharpest here. 600,000 first printing; author tour.