Superintendent Corrado Cattani is dead. After his lover, the beautiful judge Silvia Conti, recovers somewhat from the shock over his death, she decides to take vengeance and carry on his long standing battle against the Mafia. She vows to put the unscrupulous businessman Espinosa, upon whom she lays the blame for the killing of Cattani, behind bars. Tano, who killed his wife, is already in prison; Silvia offers him mitigation if he testifies against the Mafia and Espinosa, but Tano remains silent. When Mimmo, the son of the influential Mafia-family Linori, is murdered in Sicily by an American, Masino, Silvia follows the killer all the way to the U.S., where his tracks disperse.