After many years of rambling across Europe the aging Giacomo Casanova is impoverished. He wants to return to Venice but he doesn't dare going there directly, because he was a fugitive when he left. While he tries to find a way to get a pardon he meets a young lady named Marcelina. The more he shows his affection, the more ostentatiously she rejects him. Even so he doesn't give up on her because her lover Lorenzo has grave gaming debts. In return for the required money Lorenzo tells Casanova about a looming secret rendezvous with Marcelina. Moreover he lets Casanova take his place. Undercover of the night Casanova finally seduces her. Lorenzo later feels his honor was besmirched and demands satisfaction.