Revealing mistake: In the scene where Doc Brown is following Biff into the tunnel, as Marty starts to pass between the cars on his hoverboard, one of the wheels on the rig supporting the hovering DeLorean is visible. (01:30:30)
Revealing mistake: When the mother gets into an accident after her tire blows, the ghost shows up. It is floating above her car. Notice the seam where the ghost is on the car. When the scene shakes slightly, the ghost shakes too indicating it was a poorly superimposed shot.
Revealing mistake: The graphic display showing the Enterprise lowering shields is actually just a repeat of the earlier display showing the vessel raising her shields...played backwards. The giveaway is the screen still reads "Activating Deflector Shields" even though Scotty is supposed to be dropping them.
Revealing mistake: The scene where Eugene Hunt is loading his weapon in the bathroom there is a very clear shot of him loading rounds and the primers on every round are dented. Indicating that the round has already been fired.
Revealing mistake: When Spitz is stabbed with the pitchfork, you can see the line where the fake chest is. It's a different color.
Revealing mistake: When the Joker is having the party with all the balloons, Vicky Vale tries to escape from the gas by getting into a car. If you look at the back window while she is driving off, the window is rolled down, which would have led to her death, not to mention motor vehicles are not air tight to begin with.
Revealing mistake: In one shot when Alice is in the shower, as she turns for the soap you can tell she is wearing brown underwear. (00:03:30)
Revealing mistake: When Dana is walking down one hall with Leroy and a bottle of champagne, the exit sign is reversed. (00:53:05)
Revealing mistake: When the windshield is shot up, Riggs knocks the glass off the car. But interior shots that follow show Riggs' tall, fluffy hair isn't moving at all in the high-speed air rushing into the car. (00:02:15)
Revealing mistake: At the end of the movie when they reach the surface, you can see that the horizon is nothing but a big wall with the sky painted on it. You can see the water splashing up against the wall.
Revealing mistake: In the shot where Barbara is cartwheeling down the stairs after Oliver wrestles the ornament from her in the previous shot, the stairs have become totally flat like a ramp.
Revealing mistake: Double Deuce is in Jasper, MO, but this was filmed in California. After Dalton tells Tilghman that Brad Wesley was not afraid, it cuts to Dalton driving. In the background, at the left there's a sign for "Magic Mountain Pkwy" and at the right the California State Route 126 sign that reads "126 West, Ventura." After the Ford dealership is destroyed, another sign in the background reads "Los Angeles, Bakersfield" (the I-5 North to Bakersfield and I-5 South to Los Angeles). (01:25:55)
Revealing mistake: When Lupe Lamore puts Sanchez's iguana down on the table near the end of the movie, you can see the iguana bounce slightly. Also, it isn't breathing.
Revealing mistake: When Dave and Walley are running with a car, Walley says that he heard some shots. Dave replies that he didn't hear anything, but as you know Dave is deaf, and he reads Walley's lips each time he speaks. In this scene, he wasn't looking at him, but answered. (00:47:45)
Revealing mistake: When Cash stuffs the grenade in the trousers of the guy with the ponytail and throws him down the stairs, you can see that the explosion doesn't come from the grenade but from the hall on the right side of the stairs.
Revealing mistake: After the water tentacle sequence, Coffee brings Schoenick back to their bunks to get the submachine gun, so they can take over the rig. The bag containing the gun is stashed behind some pipes up by the ceiling. Watch when he reaches behind the pipes to grab the bag--the pipes move at least six inches. (01:31:57)
Revealing mistake: When Briar is reloading cartridges in the flop house, he's removing powder from an already spent shotgun shell. The primer is indented.
Revealing mistake: In the scene at the graveyard, after the Warlock assembles the Grand Grimoire and commands it to say God's true name, the fake headstone behind him starts to fall over. (01:33:02)
Suggested correction: Other headstones can be seen falling before this scene.
Revealing mistake: A brawl in the bowling alley erupts, started by Tex Cobb tossing on the ground a bad Jay Leno stunt double (hair color does not even match). (00:58:40)