In the final instalment of Sally Christie's Mistresses of Versailles trilogy, Jeanne Becu, a woman of astounding beauty but humble birth, works her way from the grimy back streets of Paris to the palace of Versailles, where the aging King Louis XV has become a jaded and bitter old philanderer. Jeanne bursts into his life and, as the Comtesse du Barry, quickly becomes his official mistress. After decades of suffering the King's endless stream of Royal Favourites, the princesses of the Court have reached a breaking point. Horrified that he would bring the lowborn Comtesse du Barry into the hallowed halls of Versailles, Louis XV's daughters, led by the indomitable Madame Adelaide, vow eternal enmity and enlist the young dauphiness Marie Antoinette in their fight against the new mistress. But as tensions rise and the French Revolution draws closer, a prostitute in the palace soon becomes the least of the nobility's concerns.