How is good and evil represented in Mulholland Drive?
David Lynch's 2001 film Mulholland Drive was originally a TV pilot, but when networks rejected it he filmed new scenes and released it as a full movie. It is a non-linear story concerning morality, paranoia, and integrity in the film industry.
There are many interpretations of the story. In most, large chunks of the narrative are fantasy and never really occur, so the events in them cannot be said to influence either good or evil; however, they do represent the main character's view of morality, assuming the main character is Diane. Diane is consumed with revenge over her humiliation at the hands of Camilla, whom she loved and who rejected her. Her action -- paying a hitman to kill Camilla -- is presented as evil in its context, but she has justified it with an elaborate fantasy in which there are more people involved. Interestingly, the killer himself is not presented as evil, since he is doing a job, but Diane tries to avoid her guilt, and so her morality is in question.
In the world of the fantasy, there are many characters who exist solely to justify Diane's actions. All of these characters are personalities created by Diane's mind; she knows that what she did was wrong, but she cannot admit it, and so hides behind layers of guilt. As each layer is stripped away, Diana is forced to confront the evil in herself, grown by jealousy and shame.