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.
Revealing mistake: While Akeem is getting his hair cut, you can see the reflection of the white character he plays in the mirror. It is quite obviously a stand-in, with a fatter face and different glasses. (00:33:45)
Revealing mistake: When they are at the Nutmar camp in the mountains, Val Kilmer tells Willow "Get on that shield!" but when they go over a 6, 7, 8 foot drop when they are sledding down the snow, you can clearly see runners on the shield.
Revealing mistake: When the guys are driving down the road, you can see Michael isn't under the truck. Yet 2 minutes later, he climbs in the bed. (01:16:25 - 01:18:10)
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.
Revealing mistake: When Hans discovers the first bad guy lying dead in the lift ("Now I have a gun - HO HO HO!") and pushes his head, the corpse is moving his head before he is hit (watch carefully). He also closes his eyes before Hans makes contact. (00:39:15)
Revealing mistake: When the weasels are at Eddie's apartment and Roger is handcuffed to Eddie, Roger runs under the bed and drags Eddie on the floor. As he pulls him you can clearly see a board with wheels under Eddie that is pulling him under the bed. (00:38:50)
Revealing mistake: When they show Heather Chandler in her casket in the funeral scene and everyone is praying, she's clearly breathing.
Revealing mistake: Adam and Barbara aren't supposed to have reflections, but when they enter the recreation of their home (just before they meet Juno), their reflections are shown perfectly in the glass display case that holds Delia's sculptures, behind them. (00:32:55)
Revealing mistake: When Charlie and Daisy get the flat and have to hitch-hike, and Daisy takes off her shoes to run to the car that has stopped, the bottoms of her feet are already filthy (presumably from having to do the scene over and over).
Revealing mistake: In the final scene as Doc tell Billy good-bye if you look up to the top right hand corner of the screen you can clearly see a jet trail in the blue sky. Certainly not possible in those days. (01:42:20)
Revealing mistake: Any time when the two girls are in hell's corridors and running around, you see these corridors as stone walls, yet whenever they back up against one of these walls, you can clearly see they are merely rubber sheeting overlayed on a framework as the rubber sheeting bends and contracts very clearly.
Revealing mistake: In the scene where the bodies are found in the river, Tom Berenger yells, "Sarah". As he looks down the river in the "wilderness" a logging truck can be seen driving down a road.
Revealing mistake: During the big fight scene, you can tell easily that Frank is wearing knee pads (try looking when his pant leg is wet). Construction workers will often wear knee pads for work but most often they wear them on the outside of the pants to save the knees of their pants. (00:58:50)
Revealing mistake: When Les' mom is doing the laundry and "finds" the Test Failed notice, you can see that she actually had it in her hands the entire time. She transfers it from one hand into the other, then puts the hand with the paper into the pocket and pulls it right back out, then knocks it off onto the floor, and acts surprised.
Revealing mistake: Near the end of the film, a B-52 seen flying across the screen. The bracket holding up the model is visible.
Revealing mistake: After her brother's death, there is a scene in which Alice starts practicing with her brother's nun-chuks. They never show the real actress doing the tricks; instead, they cut to an angle from behind her and show a double who has darker, shorter hair than the real actress and is a bit bigger. (00:56:45)
Revealing mistake: In the barber shop scene at the end of the film, Agent Anderson terrorises Deputy Sheriff Pell (who has a full head of hair) with a razor blade. Anderson throws him across the room, but the person being thrown across the room has a mostly bald head.
Revealing mistake: When Hightower throws his frisbee to Proctor and sends him flying, Proctor starts flying away before he catches the frisbee.
Revealing mistake: As Reg fights with one of the baddies with the chainsaws, as the baddie take a swing with the chainsaw he misses and cuts into the wooden door. You can clearly see that a vertical cut has already been made in the wood though, to help the chainsaw get in and cut. (01:17:55)