Agnès, the duke's daughter, has been engaged to crown prince Lucile since childhood. While the engagement was purely political for the crown prince, Agnès fell in love with him the moment they first met. Lucile, however, does not return these feelings and now that they are adults, he wishes to break off the engagement and marry the one he truly loves, a sweet and innocent noble lady. Agnès, however, will not go down so easily...