Paris, 1761. Brilliant young Parisian police commissioner Nicolas Le Floch works under Monsieur de Sartine, the Royal Lieutenant General of Police. Louis XV's kingdom is plagued by conspiracies and murders. With the help of his faithful subordinate Bourdeau, Nicolas solves mysterious disappearances and sorts out awkward scandals. From seedy taverns to the muffled hallways of Versailles, from brothels to the Châtelet prisons, he tracks and stakes out suspects, questions witnesses, gathers evidence, foils traps, and unveils plotters. Nicolas investigates the mysterious death of Viscount Lionel de Ruissec. Did he kill himself, or was it murder? His father, the ostensibly pious Count de Ruissec, doesn't believe in the suicide theory. And what about Madame de Pompadour, and the mysterious woman in blue glasses?