Revealing mistake: When they get back from Bunyans and the garbage is on the floor, Chet runs to the bathroom. The family and Roman follow him, you see Dan do a 3 count for everyone to run back In screaming, the blocking of that shot included a gap that you could see them off camera right.
Plot hole: At the end of the film Mardukas reveals that he has been wearing a body belt packed with cash - "in the neighbourhood of three hundred thousand dollars" - ever since Jack detained him in New York. Are we to assume that Jack Walsh, an experienced, hard-bitten ex-police officer, now a bounty hunter who routinely chases down violent and armed bail absconders who would kill him without a second thought, didn't even perform a perfunctory search of Mardukas when he detained him? This man used to work for the Mafia! What if he was carrying a weapon? A body belt with three hundred one thousand dollar bills in it would be uncovered by even the most casual pat down.
Plot hole: Shortly after the robbery, Kevin Kline and Jamie Lee Curtis get together in a little flat and Kline calls the police from a landline to tell them who committed the robbery. In England this would immediately lead the police to the flat from which the call was made, and the person reporting the robbery would be the first person the police would want to find and speak to. Otto has handed it to them on a plate. (00:12:29)
Continuity mistake: Rachel throws a couple of suitcases and Jamie throws 2 more and a sleeping bag down the stairs. Next shot shows a chair and boxes that were never thrown. (01:08:10)
Other mistake: When Brian takes a picture of his friend Doug on the boat, the picture shows Doug in a different position than that of when the picture was taken. (01:21:30)
Continuity mistake: After he climbs out of the air duct, John McClane's shirt goes from white to green. The dirt and grime from the air duct would cause discolouration only where the shirt comes in contact with the duct. However, his shirt is uniformly green including places that wouldn't make contact and it is impossible for all surfaces to make contact even in small areas. (00:23:05 - 00:56:30)
Revealing mistake: After Jim's horse is shot from under him while running down the really steep hill, and Jim later regains consciousness, before he turns and finds his horse dead, if you watch closely you can see the horse still breathing.
Continuity mistake: While this movie is so bad and full of mistakes, its barely worth finding them all, one stands out in the history of movie mistakes. One of the officers on board the ship, Lt. Lamont, is killed by the villain. A few scenes later she shows up on the bridge as an extra.
Continuity mistake: During the horse and buggy ride to the church through downtown New York, when one of the girls is holding the reins by herself, you can tell there is a person under a red blanket at her feet (I guess to protect her while filming in case something goes wrong,) and only a moment later, the same blanket is black.
Continuity mistake: In a bus scene Crash is shown holding a guitar talking about being in the majors. In one scene he's just holding the guitar, the next he has a pair of sunglasses in his hand while holding the guitar. The next scene the sunglasses are gone. A couple of shots later the guitar is sitting in the seat next to him. When Laloosh challenges Crash to a fight, he's holding the guitar again.
Continuity mistake: There is a scene where the kids are being chased in a speedboat, while mortars are being launched at them from behind. One shot is of the young boy looking at an incoming mortar over his right shoulder, yelling "Look Out!", and then seeing the mortar hit on the left side of the boat.
Continuity mistake: In the scene in the restaurant where Tom Cruise and Dustin Hoffman are trying to order breakfast, Hoffman's character fixes the salt and pepper shaker a certain way. In the next shot they are opposite the way he fixed them. Then in the next shot they are back to the way he had fixed them. (00:37:15)
Visible crew/equipment: In the scene where the souls are coming out of Freddy's chest, in the first close-up on the bottom left of the screen you can see a man's hand holding a black stick to manoeuvre the little arms. It's real fast but noticeable on standard play. (01:20:45)