Was Grace Kelly murdered by the Mafia? Prolific novelist and Mafia expert Waller (The Mob: The Story of Organized Crime in America; Embassy) creates San Sebastian, a principality parallel to Monaco, as the setting for his absorbing Grace-is-about-to-be-murdered ""true-life"" melodrama. At first this all seems in terribly bad taste. But Waller's journalistic background and novelistic finesse come together in a thriller that charms the reader out of resistance. Grace is now Faith Brennan, the film star who abandoned her role as a make-believe movie princess while it was at its peak to become the real-life princess of San Sebastian and acting conscience of the Gulda (Ranier) clan. She is the one who will not allow Prince Florian, her husband, to finance an economy-saving harbor-dredging project by a loan from the Vatican that she knows is actually a loan from the Mafia. Before Faith appeared in San Sebastian, the Gulda clan was deeply in hock to the Mafia. Then Faith's father, Eamon Brennan, a hard Irish titan, got the tiny nation onto a firm financial footting and removed it from the fingers of the Mafia. For 20 years Faith has kept Florian from slipping back into the Mafia's clutches. But because the Mafia cannot let even one gambling spot on earth exist outside of its dominion, Faith is being undermined. Through her old ""friend,"" Mafia-controlled singer Maggie Rose, a half-witted Mafia-sponsored tennis player elopes with daughter Polly (read Caroline). Faith's terrible secret is that she once discovered Maggie and father Eamon smearing each other in a vile act of coprophagy. Meanwhile, Faith's best friend, movie director Billy Ritz (Billy Wilder), explains to her the significance of that incident in Freud's little world. And the reader wonders: Will the brakes in Faith's sky-blue Jaguar fail on the sharp curves of San Sebastian? The novel's dust jacket shucks this as ""Europe's murkiest royal tragedy"" and suggests that crime-reporter Waller based his novel on fact. Fact or not, it's compelling, and the Wilder-Ritz character even brilliant.