Adriano Prosperi, a bank teller working in Milan, has spent years planning to steal a large sum of money and then disappear without leaving any trace of his existence. In collaboration with Giulia, his lover, he kills her husband who bears a striking resemblance to him, carries out the robbery and then burns his car with the dead husband's body inside, making everyone believe a non-existent accomplice killed him and then escaped to Switzerland. Tilde, Adriano's wife has been living separately to him for these three years and who is in a relationship with the manager of the company he robbed, isn't totally convinced, and doesn't hesitate to identify the remains of the man 'burnt in the car' as her husband. Everything seems to be going well for everyone who is directly or indirectly interested in the case, when a foolish mistake, committed by Adriano in his preparation and execution of the robbery, leads the police investigation to identify those actually responsible.