Synopsis
William Wilson, a corrupt and young aristocrat, has always been harassed by another person looking himself. Since he was a child, this homonymous character has turned up to prevent his faults and condemn his evil actions. The film starts in Rome when-after a flashback recalling the unwanted intruder-Wilson is to carry out one of his deeds: to seduce a young Duchess married to the man he is willing to take revenge on. Thus, William tries to lure his hated pursuer, who eventually becomes visible at Duke di Boglia's masked ball and is arrested. In one of the palace deserted chambers, Wilson challenges his double to engage in a sword fight...