The young Mathilde de Marsan, believes she is in love with a singer, Philippe Mazières, and steals his photo. This one, who had written a song start, searches for this photo as far as the castle of Geoffroy and Estelle de Marsan, where Mathilde's uncle and aunt take him for the husband of one of their guests, Claude Cartier. and will finally marry her while Georges, Claude's ex-fiancé will fall in love with his hosts' niece, Mathilde.