While traveling in Italy, Marlena De Blasi happens upon a somewhat ruined castle in the mountains of Sicily where she is befriended by Tosca, the patroness of the villa.  Tosca, an elegant and beautiful woman, recounts her lifelong love story with the last prince of Sicily descended from the French nobles of Anjou.  "That Summer in Sicily" re-creates Tosca's life, from her impoverished childhood to her fairy-tale adoption and initiation into the glittering life of the prince's palace, to the dawning and recognition of mutual love.