In the realm of appearances, monsters are not what we think. The Louvre, 1655. Catherine Beauvais, known as Cateau, la borgnesse, displays her striking ugliness through the corridors of the most beautiful palace in the world. Catherine has unique knowledge of plants thanks to the recipes passed down by her grandmother. But amid the stucco, velvet curtains, oak floors, chandeliers, and extravagant decorations, her ugliness, which would become legendary, and her proximity to the queen, attracted all kinds of vileness. Courtiers mocked her, tried to discredit her, the influential Mazarin hated her, and people at court wondered how such horror could have penetrated the royal palace. Thanks to her knowledge and the talent she demonstrates in using it, she becomes indispensable and even gains the confidence of the one who holds supreme power, the young king.