Summer 1572. The young Pierre de Siorac, son of a Huguenot nobleman from Périgord and a newly qualified physician, is forced to flee to the capital - threatened with the death penalty because of a duel - to beg the king's mercy. He is tolerant in his faith and quick-witted, cunning and intelligent in life, with an irresistible charisma for women - talents that are of great use to him in his perilous undertaking. He gets to know the Paris of the little people, but also the magnificent, gloomy Louvre. He courts high ladies who are true coquettes. He meets the favourites of princes and the great minds of the time. It is thanks to his skill that he is finally presented to the king and obtains his pardon. - But a murderous religious war between Catholics and Huguenots has been raging in France for ten years, reaching its bloody climax on the night of 24 August - the wedding night of the Catholic king's daughter Marguerite with the "heretic" Henri de Navarre. And Pierre de Siorac is also drawn into the maelstrom of Bartholomew's Night.