Cousins to the King of Navarre, the Cleves sisters witness the glamour and danger of the French royal court firsthand. Middle sister, Catherine, is married to the Duc de Guise, the most rabid Catholic in France. Ambitious and well-connected, Guise is the main rival for the French throne, which is currently occupied by an unpopular Henri III. Guise managed to win concessions from Henri, but concessions come with a steep price on his head. As his Duchesse, Catherine is in a dangerous position of her own. Determined to play her part in bringing about the downfall of the Valois and the rise of the Guise, Catherine will risk her own safety. But is the risk worth the rewards? Will either of them escape with their lives? Catherine has to take a chance for herself, and the consequences will change French history.