One Night, a young woman leaves her son, Cassanova to live with his grandmother. His mother hates his mother, because she works as a prostitute. And, his mother promise to him that someday she will come back to him.

A few years later Cassanova have grown into a handsome figure of a man. He is notorious for having an affair with many women in the city of Venice. The Doge as the ruler of Venice, is sympathetic to Casanova, but cannot be too kind to him  to avoid trouble with the church. He warns Casanova that he must find and marry a woman soon to get the notorierity off him. Casanova is paired with the famous virigin of Venice, Victoria. But, as soon as he meet Francesca, he fell in love with her,  the one who uses a man’s name, Bernardo Guardi to illegaly writes illegal feminist books and argues for women's rights as Dr. Giordano de Padua.

 Her mother pushes her to marry Paprizzio, a fat and older, and also rich man from Genoa whom she has never seen. When Paprizzio arrives in Venice, Cassanova lies to him and says that the hotel he booked is closed and he persuades him to stay at his house. Casanova also lies and says that his nom de plume is Bernardo Guardi. While Paprizzio, preparing to visit Francesca, stays at Casanova's house, Casanova visits Francesca, pretending to be Paprizzio.

During the Venetian Carnival, Casanova confesses his true identity to Francesca, which makes her angry. Casanova is arrested by the Venetian Inquisition for crimes against sexual morality, such as debauchery, heresy, and fornication with a novice. He saves Francesca by pretending to be Bernardo Guardi, which impresses her very much. At his trial, Francesca reveals that it is in fact she who is Bernardo Guardi, and both are sentenced to death.

When Casanova and Francesca are about to be hanged in the Piazza San Marco, suddenly a cardinal come and announced that the pope give amnesty to all of the prisoners. Not long after that, it is discovered that the "Cardinal" who gave the announcement was actually an impostor who happens to be Casanova's stepfather, wedded to his long-lost mother who came back for him just as she promised when Casanova was a child. All of then run from the venetian inquistion and use Paprizzio's boat to escape. Francesca's brother, Giovanni , stays behind in Venetia to continue the legend of “Cassanova” and become the Cassanova himself.