Continuity mistake: Alex takes the cigarettes out of her bag twice when she and Dan have lunch in the restaurant.
Continuity mistake: In the scene where Michael Douglas is listening to the answering machine look at the towel to the right of the paper towel rack. It is moved the next time you see it. (00:22:15 - 00:23:05)
Continuity mistake: When it looks like Alex is dead in Dan's bath, she has a long strand of blood coming out of her mouth, but a second later it's gone, and her eyes, which were white, are no longer white - they are open and look like normal eyes.
Continuity mistake: When Michael Douglas is listening to a "deposition" (which is really Glenn Close calling him names, etc.) using his ear phones in his new attic home (just before his wife comes up and finds him), the audio tape is not the same one as he was listening to minutes before in the car! The words are almost the same but the inflections are different.
Suggested correction: It is the same tape, although a mistake does remain - the tape when first being played in the attic is a few sentences before where the tape should start (without him rewinding it at all).
Continuity mistake: The water level was almost but not quite overflowing the brim of the tub when Michael Douglas is pushed in, and the faucet was still running, so there should have been more water on the floor. (01:52:25)
Visible crew/equipment: In the library, right after Dan breaks into Alex's apartment, a cameraman's reflection is visible in a window as a librarian pushes a cart past it.
Continuity mistake: Dan plays the tape that Alex made in his car. He stops the tape when he gets home, and after he gives his daughter a pet rabbit, he goes to his den and puts the tape in the tape recorder and presses play - that's all; he doesn't rewind it - but what he hears is the same bit he heard in the car, which is wrong; the tape should have started play where it left off in the car.
Continuity mistake: Playland, Rye NY in the spring, summer and autumn. Alex and the girl walking to the Dragon Coaster. It's spring with the leaves in bloom. Then in stock footage of a different roller coaster being pulled to the top, it's fall with the leaves a golden yellow. Then in other stock footage, the trees are a lush summery green. (01:36:35)
Continuity mistake: The amount of blood on Dan's face, when Alex slits her wrist, keeps changing.
Visible crew/equipment: In the beginning of the movie as Michael Douglas runs to answer the phone someone has knocked the overhead lamp in his kitchen and set it swinging. (00:03:05)
Continuity mistake: There is a lot less blood on the knife after Glenn Close flings it than there was in the shot before when you see her fall. (01:51:50)
Continuity mistake: Fred Gwynne's pipe jumps from his hand to his mouth when he and Michael Douglas walk up the stairs to his office.
Visible crew/equipment: The shadow of a crew member goes across Michael Douglas' shirt as he's sitting on the couch reading in the beginning of the movie. (00:02:25)
Continuity mistake: In the scene in the tub, Glen Close's feet start out filthy, then they become clean as a whistle when she is flailing from her knees, then by the end of the scene they're disgusting again. (01:52:40)
Continuity mistake: As Michael Douglas listens to the answering machine, the green overhead lamp that is above the table in the beginning of the movie is gone. (00:22:20)
Visible crew/equipment: A shadow moves to the left of the refrigerator when Glenn Close says "I'm pregnant I'm gonna have our child." Michael Douglas doesn't move out of his position yet. (01:08:30)
Continuity mistake: At the start of the film we are introduced to Michael Douglas' family life. His wife is in the bathroom getting ready for their night out, Michael is sat on the couch reading and his daughter, Ellen, is sat on the chair watching cartoons. In one shot Ellen is sat on her own, but in the next shot their dog has magically appeared on her lap.
Continuity mistake: The amount of wine in the Michael Douglas' glass changes in the scene where he is talking to his daughter about rabbits. It fills up without being touched. (00:41:30)
Plot hole: In the kitchen, when Michael Douglas is preparing the hot water for the tea just before the final bathroom fight, there is a shot of him looking up at the ceiling and noticing the leaking water (obviously from the overflowing bathtub). But, he turns back toward the stove and continues to prepare the tea, instead of having an immediate reaction that something is wrong. It is not until the teapot whistles, and his wife screams, that he realizes something is wrong. He should have run up stairs as soon as he noticed the water leaking from the ceiling.
Continuity mistake: (DVD only) In the new ending, when Alex attacks Beth at the family's home, Beth has bruises and a cast on her arm, obviously a result of the accident she was in a few days ago. In the original ending, presumably taking place within the same time frame, when the cops come to question Dan about Alex's death, Beth is fine - no bruises, no cast, she doesn't even look tired.
