Women in Cell Block 7 (1973)

To save her father, Carmelo Musumeci, whom a gang of drug traffickers accuse of making 20 kilos of heroin "disappear," young Lilly is incarcerated--insulting two traffic police officers--to get in touch with a girl, Daniela Vinci, who knows how things really went. Ignoring that her father died falling from a ruined house trying to escape the gang, Lilly manages to wrest the drugs from the young woman after some futile attempts, and while mysterious recluses, with a supervisor's complicity, terrorize Daniela to prevent her from speaking. But knowing the truth will be of no use because, warned by the prison's director, a faithful servant of the drug traffickers will--after his release--kill both her and the police commissioner to whom he had entrusted the information obtained by Daniela.