Giovanna is a beautiful girl, but she has problems with men: everyone just wants to use it, even her fiancé Claudio. He'll find a way out by becoming a traffic cop. Like Joan of Arc, her idol, she will not look at anyone and with help from the magistrate Patane', who is in love with her, she will unmask a series of tangles and corruption and will even denounce her boss, Marcellini. The two champions of justice will crown their dream of love, transferred to a distant island south of Sicily, but the corrupt will remain in their place.