Amore e sangue (released in the U.S. as "City of Violence"), the 1951 Marino Girolami (billed as "John Wolff") West German/Italian romantic action adventure war thriller.
After serving their sentence, three prisoners, a doctor, a civil servant and a thief, leave jail. During the train trip they do together to return home, they analyze their respective lives. The doctor has been required to perform an operation on a child abandoned by his father, a millionaire.
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.