Aldo Morosini, a Venetian prince and antiquity expert, is passionate about the search for four priceless stones of a sacred relic. The story of the third of them, a beautiful opal, turns out to be connected with the most romantic woman of the Austrian dynasty - Elizabeth, the wife of Emperor Franz Joseph. The prince's search for the stone leads him to a mysterious masked woman. Thanks to the help of the one whom the prince loved more than life itself, he finds an opal, loses his beloved, but not his love! Their story is not over yet...