In the prison of San Vittore there is, among other detainees, a strange type that they call "Il Cavaliere". The latter suffers a conviction for theft and his fellow prisoners have a certain respect for him.
In the eighteenth-century Rome, Don Pasquale Corneto, wants his young nephew Ernesto, dedicated to a wasteful social life, to marry a rich spinster, both to save on the expenses of his maintenance and to increase the family heritage.
Eva Bianchi, who works as a manicure in a beauty salon in Milan, falls in love with the owner Adamo Rossi. But Adam, who at first always gives her roses, now no longer seems interested in her.
