As Anne Perrys New York Times bestselling novels always remind us, she is a matchless guide to both the splendor and the shame of the British Empire at the height of its influence. In her twentieth William Monk mystery, she brings us to Londons grand Mayfair mansions, where the arrogant masters of the Western world hold swayand to the teeming Thames waterfront, where one summer afternoon, Monk witnesses the horrifying explosion of the pleasure boat Princess Mary, which takes nearly two hundred of the merrymakers on board to their deaths.The tragedy is no accident. As commander of the River Police, Monk should handle the case, but the investigation is turned over to the commissioner of the Metropolitan Police. An Egyptian man is swiftly caught, tried, and sentenced to die.