Safer in a Motel
After fleeing Phoenix with her boss's money, Marion spends the night sleeping in her car on the side of the highway. When the patrol officer wakes her up, he tells her, "There are plenty of motels in this area, you know, just to be safe." This is ironic because the following night, Marion does check into the Bates Motel - and that is where Norman Bates murders her.
Sam's Letter
Marion's only reason for stealing the $40,000 is so that she and Sam can get married; he is delaying matrimony for financial reasons. After Marion's death, however, we see Sam writing a love letter to Marion in which he reverses his conditions and agrees to marry her even though he is broke. The irony here is that it is too late; Marion has already stolen the money, which has led to her shocking death.
Marion's Shower
After her conversation with Norman Bates in the parlor of the Bates Motel, Marion decides that she is going to return the money and "come clean" - take responsibility for her crime. She takes a shower, which is a symbol of rebirth and baptism. However, while Marion is in the act of cleansing herself of her guilt, Norman murders her. Marion's realization of her mistakes ironically ignites Norman's latent madness, sinking her deeper into her trap instead of freeing her from it.
Marion's Freedom
Even though it is "ironically unjust" that Norman kills Marion just after she has decided to return the cash she stole (Kolker 90), his murder of her ironically transforms her from a criminal to a victim. By the time Sam, Lila, and the police find out the truth about Norman, nobody is blaming Marion for running away with the money because Norman has committed a much more damaging crime. His crime is motivated by something more twisted than typical crimes committed for greed or passion. In this way, Norman's murdering Marion actually does free her from guilt.
