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)
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.
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: When Alex goes to see Dan in his office, Dan in the first scene is sitting with uncrossed legs, then his legs are crossed, then uncrossed again.
Continuity mistake: In the party scene the people behind Stewart Pankin on the slow moving food line change it just a matter of seconds from shot to shot. (00:04:50)
Continuity mistake: In the very first scene we see Ann Archer pulling down a shade from afar with the curtains pulled to the side. Then we switch to her inside the apartment and see the curtains are already closed. (00:02:00)
Continuity mistake: Quincy is sleeping on the little girl and keeps changing positions on her lap. (00:02:10)
Continuity mistake: The part in Stuart Pankin's hair keeps changing in the party scene. (00:05:40)
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 little girl appears to have been given a haircut after we see her at the empty rabbit cage, most apparent when we see her the following morning. (01:27:00 - 01:30:30)
Continuity mistake: Early in the movie, there is a black clock on the wall in Dan's kitchen that reads 7:50. Later, when he is in Alex's apartment strangling her, the same black clock is now in her apartment and it, too, reads 7:50.
Continuity mistake: When Michael Douglas comes home the first night after being a bad boy with Glenn Close, he is shown in the kitchen talking on the phone to his wife at a little after 8:30 AM. Not only does he talk to her, but he also has a whispery chat with his lover, walks all about the kitchen, sits at the table, and the time on the clock doesn't change once. (00:22:20 - 00:23:05)
Continuity mistake: At the end Michael Douglas is standing in front of his home with the door open in the background with the hallway illuminated. The camera angle now switches to inside the house, but he has to enter the house through a closed door.
Continuity mistake: When Dan throws Alex into the bath, she goes in face down, but suddenly she is face up - which would be a difficult manoeuvre in a small bath.
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 Alex, naked in bed, jumps up to stop Dan leaving, she attacks his shirt, and you can hear it ripping, but, later, it's completely fine - no ripped bits anywhere.
Continuity mistake: When Dan leaves the budget office in his rental car, the front license plate is mounted off to one side, unusual for this type of vehicle. When he arrives at the house, it's still the same license plate number, but the plate is now mounted on the centre of the bumper.
Continuity mistake: When Dan's wife is by the dinner table talking about the house, his arm is up, yet a frame later from a different angle is down.
Continuity mistake: Dan throws his umbrella and it bounces on the edge of the wastebasket but lands on the floor. When he walks next to the wastebasket the umbrella is now inside.
Suggested correction: It lands on the ground and stays there.
