A young woman (Helen McCrory) tearfully leaves her son (Eugene Simon) to live with his grandmother and promises to return for him someday. Several years later, in 1753, in Venice, Casanova (Heath Ledger), is notorious for his promiscuity with women, his adventures being represented in puppet theatres around the city. The Doge of Venice (Tim McInnerny), the ruler of the city, is a friend to Casanova, but cannot be too lenient on him as he wishes to avoid trouble with the Church. He warns Casanova to marry soon, or he will be exiled from the city. Casanova gets engaged to Victoria, famous for her virginity, to save himself from exile.