Based on a popular Neapolitan song, ‘A santanotte, is the earliest extant feature film by Elvira Notari, Italy's first and most prolific female filmmaker. Nanninella, a young girl, is exploited and abused by her father, whom she maintains with her waitress salary.
In order to conquer Margaretella with expensive presents, a young man called Tore steals his mother's jewels but Margaretella seems to prefer Carluccio who challenges Tore to a duel and wounds him. Forgiven by his mother just before she dies, Tore takes revenge by killing Margaretella, but even in prison he can't stop thinking to his victim.