Continuity mistake: When Christine is fixing herself after the guys smashed her up, her front end is shown to be perfectly straight for its entire width and the hood is missing. Near the end of the scene, the front end is shown crushed and unfolds again, and the hood appears from nowhere.
Continuity mistake: When Dan walks down to a podium and looks over to see the dolphin knocking at the gate, the tee-shirt he is wearing changes from being plain white with a tag badge on his left, to a white shirt with a large blue stripe across it, with a tag badge being on the right. (00:08:20)
Continuity mistake: After Norman argues with Mr Toomey, before he goes up to the house, you can plainly see the light on in the living room where Mary is sitting. When Norman goes in the house, Mary is sitting in the dark and Norman then turns on the light.
Continuity mistake: The fence at the start of the movie changes as Cujo chases the rabbit. In the shot as they run towards it, there is just one straight plank running across the bottom. When they reach it, there is now an askew, diagonal plank attached to the straight one. (00:02:00)
Continuity mistake: Henrietta Dodd shoots Johnny holding the gun in her right hand. Sheriff Bannermann emerges from the bathroom and shoots Henrietta. The film switches to slow motion as she is shot and stretches both of her arms out to the sides as she falls. When she lands, her left hand is resting next to the railing of the stairs and is covered in blood. At no time did her hand come in contact with her wound or get any blood splattered onto it.
Continuity mistake: In the airplane, the window shade in the seat next to the main character repeatedly opens and closes between shots.
Continuity mistake: When Meg comes up to Angela, taunting her, Angela's head position and the look on her face changes in each shot.
Continuity mistake: As the truck emerges from underground, it lands tearing off the front bumper. The scene cuts away for a moment, and we then see the truck turning around to face the camera, bumper intact. (01:00:10)