Marie Antoinette is just a teenager when she's forced to leave Vienna to marry the Dauphin, the heir to the French throne. She must produce a Bourbon heir to secure the alliance between France and Austria.

With Louis still not consummating the marriage after four months, Marie realises that producing an heir will not be straightforward. She turns to Madame du Barry for support and advice. However, after discovering more about the woman's past, Marie is shocked, and 'friend' becomes foe. There cannot be two queens at Versailles, and du Barry is not about to disappear.

Marie-Antoinette and Louis prepare to make their first official visit to Paris. Everything changes when the king falls seriously ill. The succession suddenly becomes a concrete reality. Du Barry knows she has to protect herself.

Against all expectations, it is Joseph, Marie-Antoinette's brother, who goes to Versailles to save the royal wedding. It doesn't take long for him to understand that he has his work cut out for him if he wants to unite this struggling couple.