Continuity: Laura runs through a downpour but is dry when she walks into the refreshment room.
Continuity: As Laura enters the apartment, the pattern of water marks on her back changes.
Errors made by characters (possibly deliberate errors by the filmmakers): Laura doesn’t pay for the brandy when arriving for the last train.
Continuity: When Laura is running away from Dr. Lynn's apartment in the rain, her book is next to her body, under her purse. Halfway down the street, the angle changes on the still-running Laura, but now the book is outside her purse. And it never gets wet!