Continuity mistake: At One Eyed Jack's, when Agent Cooper and Jacques are sitting and talking there are 2 glasses of beer on the table. In one shot Jacques finishes a glass. When he gets up, both glasses are full. (00:10:20 - 00:11:40)
Other mistake: When Cooper is on the floor after being shot, as he's signing the check, he is doing so with the pen closed, and proceeds to click it open as he hands it back to the room service.
Continuity mistake: The position of Blackie's fingers on Audrey's chin switches depending on the angle. From behind, her fingers are straight; from the front, her fingers are scrunched up/bent.
Continuity mistake: When Cooper is at the police station describing the events of the night of the murder, he is seen taking a doughnut and placing it on the napkin next to him. A few shots later his napkin is empty and the doughnut is back on the stack.
Chosen answer: Laura was killed by her father Leland, whilst he was apparently possessed by the spirit BOB. The exact manner of her murder is not clear, as several injuries found during her autopsy we later discover occurred during a separate incident before her murder. We know that she was beaten and killed in an abandoned train car, and her body was then wrapped in plastic and thrown in the river.
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