Revealing mistake: Sloth is shown with three "arms." It's most easily noticed after he wakes up. His right arm is bent at the elbow, pointing to the ceiling, his left arm is pressed tightly to his left side between his torso and the jacket used to conceal the upper part of the prosthesis, and his third "arm", the prosthesis, is bent at the elbow, hanging halfway off the bed, and pointing to the left of his body. It has several large, protruding "veins" in it and the stump where the hand should be is off-screen.
Revealing mistake: In the newspaper that Tom Cruise is reading, the same sentences are printed over and over.
Revealing mistake: Just before the truck slides off the cliff edge, you can see that the truck's cab door is open where the stunt driver jumped out.
Revealing mistake: You can see the plane intact even though it has exploded. It stays complete, there's just fire around it. (00:18:55)
Revealing mistake: When they show Heather Chandler in her casket in the funeral scene and everyone is praying, she's clearly breathing.
Revealing mistake: Early on, after Clary blasts the demon with a homemade explosion that blows a huge fireball across the kitchen and blasts out the window, there is no sign of anything being burned, not even the curtains. The kitchen is only in a slight shambles and there are small fires burning in isolated areas that never spread or char anything.
Revealing mistake: When the Hårgas begin eating their meal after Dani is crowned May Queen, there is a shot of Dani just after the Hårgas pick up their knives and forks where she is looking over at Christian. Sitting next to her is a woman who cuts her food with a knife and fork, raises the fork to her mouth and takes a bite, but there is no food on the fork. She is just miming the actions. (02:13:15)
Revealing mistake: When John tries to stop the van while Maggie is driving, because he sees the small girl in the road, as the van screeches around the road, you can see the road is covered in tyremarks from previous takes. (00:20:10)
Revealing mistake: When Ned is pretending to drown, Brenda swims out to rescue him. You can see that she and Ned stay underwater for a few seconds, until their cue to emerge. (00:23:30)
Revealing mistake: When Ratigan is sneaking up on Basil inside Big Ben, there is a shot where both characters have their backs to the camera. In this shot, there is a piece of equipment directly in front of the turning gear they are standing on. This piece of metal can be seen to flicker for a few moments.
Revealing mistake: In the gun battle following the bank robbery, Drucker fires his shotgun at Cherrito. A female pedestrian in the background (apparently unaware she's in the shot) can be seen acting casually, without any reaction to the gun battle taking place.
Revealing mistake: This is toward the end of the movie. The scene where Dr. Giggles has a waiting room full of his victims. If you watch closely, you will see the blonde corpse blink her eyes.
Revealing mistake: In the scene where Trout's gang burns the school and kills Sam, there is a part where Katherine runs into the sheriff's office then exits. A few seconds later, Katherine runs by a shop on which the name is reversed. Very obvious. (00:51:40)
Revealing mistake: At the end of the film when Ginny and Paul are fighting Jason, his machete hits the shrine where his mother's head is displayed and where Terri's body is strewn. When the machete hits, Terri flinches, even though she is dead. (01:16:00)
Revealing mistake: When Scooby, Shaggy, Mary Jane, and Daphne go crashing through the window while running from the two monsters, the falling glass and broken window frame pass right through the CGI Scooby. (00:42:30)
Revealing mistake: After Joe blows up the A-Bomb, the film is reversed for a second as is evident by Joe's "I Choked Linda Lovelace" shirt.
Revealing mistake: Just before entering Robertson's office after climbing the stairs, Spooner is behind Sonny with a flashlight. The light shines on Sonny's back and the door, but Sonny does not cast a shadow.
Revealing mistake: When Wally is firing the laser at random from the small spaceship, we see Fidget running down some stone stairs, and there are violent laser impacts directly behind him that could only have hit where they did if they had passed right though his body. (01:41:55)
Revealing mistake: In the beginning, there is a scene where Sen. Shaw is watching Raymond make a speech on a TV screen. It was obviously put in in post-production because the aide immediately next to the screen is nodding and clapping in agreement at inappropiate times.
Revealing mistake: In the scene when Christine smashed repeatedly into the silver Camaro at the gas station, there is no motor in the Camaro. The hood of the Camaro gets knocked off the hinges and is twisted sideways on the car. As Christine is in reverse and dragging the Camaro along you can see down through the hood that the engine compartment is empty. Minus a transmission also, I believe. (01:15:30)