Ottone in Villa

The Roman Emperor Ottone is in love with Cleonilla, who can't resist flirting with two young Romans, Ostilio and Caio. Ostilio is in reality a woman, Tullia, who disguised herself because she's in love with Caio. She plans to kill Cleonilla out of jealousy, but she first tries to dissuade her from her relation with Caio. Caio sees the meeting and misinterprets it as a romantic encounter. He warns Ottone, who commands him to kill Ostilio. Before he can execute the order, Ostilio reveals himself to be Tullia. Cleonilla claims to have always known it, to conciliate Ottone. He believes her and the opera closes with the marriage of Tullia and Caio.