Revealing mistake: When Carl is being dragged away by the demons, you can see the cable line that he's attached to. May be fixed on DVD.
Revealing mistake: When the new Pope is announced, the New York Times headline is shown, and 'Copyright 1990 The New York Times' is visible. The event took place in 1979.
Revealing mistake: Doug has the hologram when inside the alien nuclear reactor, and a bunch of bad guys encircle the holographic image and fire at it at point blank with automatic weapons, and not one bad guy gets hit. If they encircled the 3D image, at least a few bad guys would have been hit by their own men. (01:37:00)
Revealing mistake: When the scientists inject the mouse with poison, they put it in a jar. The, after they place it down you can see someone's hand swap the jar for one containing a dead mouse. You can even hear it. (01:17:58)
Revealing mistake: In the library scene when Richie sees Pennywise the clown, all the balloons filled with blood are popping on people who aren't supposed to be able to see them, but one lands on a lady and you can see her jump as the balloon pops.
Revealing mistake: During the big fight scene, just as Annie Wilkes falls to the floor and hits her head on the typewriter, the actress is replaced by a really bad looking Kathy Bates dummy!
Revealing mistake: When the ferret bites Dominic's father, it is a stuffed (dead) ferret. The mouth does not close.
Revealing mistake: When Melanie Griffith comes home from the jail, as she opens the door you can see there's no wall, it's just the door.
Revealing mistake: In the skywalk scene, when McClane pushes the paint stand on the terrorist, it is quite obvious that they use a dummy when the paint stand falls on the terrorist and crushes him. (00:45:05)
Revealing mistake: When the little boy steals the wig from the dead Rug Daniels' head Rug blinks and twitches his lip. (00:16:45)
Revealing mistake: During the party scene, when Jacob starts hallucinating, you can see the stick that one of the fake birds is attached to.
Revealing mistake: When Danny falls down from the ceiling, watch closely and you can see the security wire attached to his leg. (00:34:40)
Revealing mistake: Just before RoboCop gets out of the car to walk towards the baseball coach, Lewis shoots at the coach and he jumps back. Watch carefully. Whilst jumping, his hat comes off slightly and you can see the make-up for the hole in his head, which he doesn't receive for a few seconds after this. Seen best in Slow motion on the DVD. (00:50:31)
Revealing mistake: In the scene where Jack Ryan is brought aboard the U.S.S. Dallas after releasing himself from the helicopter, two crewmen drag him inside. The crewman on the left side of the passage backs into a metal valve, but the valve moves down and left, then snaps back in place as if mounted to a rubber pipe.
Revealing mistake: When Strakk is firing the giant nail gun thing at Darkman during the climax, you can see that the gun firing does not always match the squibs going off on the beams behind Darkman.
Revealing mistake: When Joanne is kneeling by Phil's body, she cries "Oh God no." and then, just before it cuts, Phil's right hand moves, even though he is dead. (00:45:50)
Revealing mistake: When Graham and Stella are in bed, the camera shows only their arms intertwined as if he's lying on top of her. She's gasping loudly in response to his thrusting, but their arms never move back and forth to reflect this, so it's clear they're not really having sex.
Revealing mistake: When Nelson first undergoes the experiment, the doctors use a small mask to put him to sleep. When he is supposedly waking up, Rachel asks Randy to help her with oxygen. He hands her the same small mask they used the first time ie. anesthetic. Just for a second she has a look on her face which says "this is the wrong mask" and she tries to hide it with her hand. For the whole rest of the film, the other doctors use a bigger mask when giving oxygen.
Revealing mistake: On the toxic plant, where James runs from the forklift coming out of the garage door, the oil drum containing Carl flips off the forklift. When the oil drum flips, you can easily see the mechanism used for flipping it. (01:17:45)
Revealing mistake: When officer Van is shot with a shotgun there is one shot in which he flies backwards towards the camera in slow motion. From this point of view the launchpad (catapult), from which the officer is thrown, is visible underneath his feet.