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: Vinnie places two coin-filled water bottles in the trunk of his car and closes the trunk. As he is walking around the car to get in, the back of the car suddenly sinks down, which by itself indicates a special effect, as springs don't behave that way. But in addition, the rear tires, which would appear flattened if under a heavy load, are completely unaffected by all that "weight."
Revealing mistake: When Larry is camping in the tree outside Ellen's house, if you look at his face before he falls it is a stuntman falling, not James Belushi. (01:03:35)
Revealing mistake: The B17 that crash lands in the beginning appears quite realistic, until during a head on shot when you can see daylight through the clear nose from a window in the back of the plane. This shows it to be model as in the real plane bulkheads would block this from happening.
Revealing mistake: Right after Xayide dies we see a shot of two monsters. One of the monsters explodes and the particles from the explosion hit the other monster making it break in half before it explodes itself. (01:15:25)
Revealing mistake: When Larry rides through the glass doors on his motorcycle, you can see the glass has been broken beforehand in order for it to shatter more easily. (00:38:00)
Revealing mistake: There are a couple times you can see the tape that marks where the actors are supposed to stand in the shot. In the beginning, when Bobby and his brother walk in on Ernest trying to get a cleaning machine to work, look on the floor and you will see some tape in the shape of a T. Bobby will move his feet to the T. Also when a criminal begs for Nash's help because he killed someone, and Nash walks forward, look on the floor to see another tape T, and what do ya know, Nash stops right on the T.
Revealing mistake: Near the beginning of the film, when Charlie and Brian steal the Honda there is a shot where Brian says "Charlie, slow down, think". By comparing the view outside of the car window in this shot to the surroundings of the previous and subsequent shots, we can see that it was filmed out of sequence, and in a different part of the parking lot.
Revealing mistake: Throughout the car chase, the same white Plymouth Volare coupe is seen over and over, sometimes parked, sometimes being passed going in the same direction, coming head-on, or getting bumped out of the way.
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.
Revealing mistake: When the Looking Glass plane is chasing Air Force One, you can see the wires holding up the model planes.
Revealing mistake: When "Krebbs" the koala is discussing with his other friends in the cell. If you look closely, you can notice a blink in the outline in the "Krebbs" nose. It's a clear ink & paint mistake of the blur line.
Revealing mistake: Steven Seagal visits his friend in Ohio. They are standing in a high school football field and you can clearly see tall palm trees in the background. This same mistake is later repeated in another street scene.
Revealing mistake: Ken is killing Diane by stabbing her with the knife. You can see that Ken is only stabbing the floor next to her.
Revealing mistake: A shot of Mel and Goldie on the motorcycle in Michigan is re-used for a shot when they are supposedly in Wisconsin. They are driving along a curving, downsloping road.
Revealing mistake: Our hero Sherman is talking to Maria's husband, and right after he tells a story he coughs and falls on the table dead. The thing is, he falls with his mouth open, but as he lays there on the table he closes his mouth.
Revealing mistake: Outside the courthouse, there is a sudden downpour and the rain is coming almost straight down. Cut to a close-up of Van Damme and the rain is suddenly heavier, coming in at much more of an angle, and it's noticeable that Van Damme is not even getting wet. Cut back to the scene where Amanda is walking away, the rain is now back to being more vertical, is lighter and this shot shows that Van Damme's hair has not been touched by a single drop of rain.
Revealing mistake: When young Norman Bates is spying through the peephole on his mother, who has brought home a man to the motel, we see him in the shower. Although the curtain is translucent, we can see he is wearing a black speedo.
Revealing mistake: When Nikita is being taken away after her sentencing, she breaks the top of the wooden bench off. However, you can clearly see it has been cut beforehand to help break off easier. (00:10:30)
Revealing mistake: When the boys use the glasses to start the fire, there is smoke coming from under the wood they are lighting. This wouldn't happen. It would come only from the focused point of light made by the glasses.