Continuity mistake: When Michael enters the Elrods' home and steals the knife, as he picks up the knife from where Mrs. Elrod had left it, there are several drops of blood that fall onto the lunchmeat, presumably from Michael's injuries from having been shot. A few seconds later when Mrs. Elrod walks back over to the lunchmeat and reaches for the knife and sees the blood, the droplet patterns are different.
Continuity mistake: When Snake kills the wrestler he falls forward shoulders forward, next minute his arms are over the ropes, next minute his arms are in a different position again - quite active for a dead man. (01:16:55 - 01:18:10)
Continuity mistake: The name patch on O'Niel's uniform changes between "O'Neil" and "O'Niel".
Continuity mistake: When Albert Johnson jumps into the top of a tree, he first throws his backpack off the hill but leaves his rifle. After he gets to the base of the tree both his backpack and rifle are there.
Continuity mistake: In the final scene of the movie, on the highway, Cora (Jessica Lange) is ejected from the car Frank (Jack Nicholson) is driving, hits the ground, dies instantly after the impact, and rolls over to the shoulder of the road. Weeping, Frank kneels by her side and holds her motionless right hand with his right hand, which, of course, has no wedding ring (They had just been married.) The next and last close-up shot shows he's holding her right hand with his LEFT HAND, the wide gold wedding ring appearing now in full sight. (01:59:33)
Continuity mistake: Jack sees the car drive into the creek and runs to check for anyone injured. Jack dives into the water and you see the car submerge completely. Jack is then looking around and the car's trunk is sticking out of the water, then submerges yet again.
Continuity mistake: When Chuck Norris is battling with the Triads at Mako's house, a oriental box is knocked off a table in the first shot when a Triad is slammed against the table it is on. In the next shot of the table, the box is back in its' position.
Continuity mistake: When Stallone and Williams are on the back of the train, Stallone smashes the window. Cut to Hauer. After this, the window is shown again, and the hole in it is larger than it was when broken.
Continuity mistake: When Ned and Maddy are discussing the whereabouts of her dead husband's glasses, the ceiling fan keeps changing speeds.
Continuity mistake: When the protagonists get in the office to talk to his client at the beginning of the movie, he's holding the bag one way outside the door, the other way around when he walks in.
Continuity mistake: 1981 film: Near the end, John Heard is riding a white horse. He has his left arm missing during the whole movie, but in one scene his right arm is missing instead as he is dashing through the woods. When he comes out of the woods it is correct again.