A cross between a family memoir written in the sunset of life and a faded Hollywood Babylon: a search for the mother of Cecil B. DeMille's youngest son. Following a quick survey of generations of de Milles and of Richard's youth and young adulthood, the mother mystery begins with a 1955 revelation. Until then, the 33-year-old Richard knew no parents but his adoptive ones, Hollywood royalty Cecil B. and Constance DeMille. Upon the death of his uncle, director and playwright William de Mille, Richard learned that William was in reality his father and that his mother was long-deceased scenarist Lorna Moon. Richard's decades-long investigation into his past revealed Moon to be a Scottish-born woman, originally named Helen Nora Wilson Low, who became a bestselling author. He also uncovered the elaborate maneuver that made him an orphan and William's brother Cecil his adoptive father, and how Lorna left two other children (Richard's half-brother and half-sister) behind to seek fame in Hollywood. Despite the wealth of rare detail (e.g., Cecil's dalliances and physical attributes; young Agnes de Mille's demeanor), the book leaves no aftertaste of titillation. Instead there is gravity, particularly in the author's final reflections on his sparkling, driven mother and the plain declaration of his purpose for the book: ""to tell a true story about some people who are gone . . . whose lines crossed one afternoon to produce their chronicler."" De Mille, whose long career has included science fiction writing and television directing, also reveals a mature understanding, concluding that his life was probably better as it was than as it might have been. But the book's sobriety has limits. Those interested mainly in Hollywood tales or the de Milles may find Low-family-related chapters overreported. Further, the author's emotional balance, seemingly natural to his age and disposition, lacks passion.