Can a good man tame a woman on the wrong side of the law? Paolo (Marcello Mastroianni) is a slightly clumsy cab driver who, not long after being issued a new vehicle, picks up an interesting fare -- a strikingly beautiful young woman, Lina (Sophia Loren), who is going to the beach with two of her boyfriends. When they arrive at the seashore, Lina invites Paolo to join them, but he soon discovers Lina is simply working her charm on him so her friends can steal his cab. Paolo takes up the matter with the police, but Lina's profoundly silly explanation of the events makes him wonder if he simply misinterpreted the whole thing. However, after meeting Lina's dignified father Stroppiani (Vittorio De Sica), Paolo discovers that both father and daughter are thieves, as is the rest of the family. As Paolo unsuccessfully tries to bring the family to justice, he finds himself falling for the beauteous Lina, and decides to marry her, certain that matrimony will bring her to the straight and narrow. Peccato Che Sia una Canaglia (released in America as Too Bad She's Bad) marked the first time Sophia Loren (then only twenty years old) was co-starred with her frequent screen partner Marcello Mastroianni; they would eventually make thirteen pictures together.