Revealing mistake: At the end of the film Vanessa gets crazy because Bob kills her grandma, and she starts beating him up in the caravan, hitting him and throwing various stuff at him. Throughout the scene, Reese Witherspoon's' stunt double is really obvious. Her hair looks completely different!!!
Revealing mistake: After Draco flees the cave, Bowen is riding his horse in the water after him. You can easily see that it isn't Dennis Quaid but his stunt double.
Revealing mistake: After the second movie sign, when everyone gets into the theater and sits down, there's a very obvious cut, as all the characters cut immediately from the position that they sat down in to a completely different position. (00:28:05)
Revealing mistake: After Lucy discovers Mrs. Bradley in her bed, as she fights off and runs from Patricia, it is obvious that she wears knee pads for these shots.
Revealing mistake: When Liam Neeson is on the boat on his return from England there is a shot of the water and part of the boat where you can see a modern CCTV camera on the side of one of the masts - rather advanced for the time the film was set. (01:21:20)
Revealing mistake: When Daniel drives the van out the mall windows one window is left unbroken on the left side. All the windows around it are shattered.
Revealing mistake: In the mansion where the two flunkies are chasing the puppies that are to be skinned, one of them flies off the roof, through the stone battlements and crashes into a frozen pond. You can clearly see the stonework landing around him in the pond and bouncing/floating.
Revealing mistake: It's very clear they blew up a model of the buildings. The grass seen just before the explosions is way too long and is not as long when the characters are running away. Further, the truck and the barrels have disappeared at the explosion shot.
Revealing mistake: When Robert Stack introduces himself in the hotel room he says he is an A.T.F. agent, but the ID he shows says F.B.I. (00:26:45)
Revealing mistake: Throughout the movie the rescue helicopter changes. The paint job remains the same but they're two entirely different choppers. This can be most easily seen by the flat single-pane windshield of one and the round wrap-around windshield of the other.
Revealing mistake: When taking the driving test Ashtray is driving down a street with on the left a parked white RV. After making a left turn, we see through the rear window he's driving down the same street.
Revealing mistake: When Le Merchant is offended by his wife's comments and puts the Lament Box into the travel chest, a section of the gold veneer on it has bent upwards.
Revealing mistake: When the Oceanic 747 attempts to make its first landing, you can tell that the 'hole' on the side of the aircraft is simply painted on.
Revealing mistake: In the scene where Romeo and Roy snap all the clubs other than the 7-iron, Roy drops his golf ball onto the grass. However, when he hits the ball, a white tee can be seen travelling up towards the top left of the screen. The tee can easily be seen but is much clearer in slow motion.
Revealing mistake: Painfully obvious bluescreen/CGI effect when Snake makes the motorcycle jump into the back of the pickup truck in Cuervo's motorcade. (00:32:45 - 01:08:20)
Revealing mistake: When the guy that was shot in the chopper is falling, you can see the protective, yet flaming mask on his face.
Revealing mistake: Towards the end of the film when Gary Sinese shoots the guys in the white van, when he shoots the bald guy, as he falls out the door you can see the squib vest protrude from under his shirt.
Revealing mistake: When the second helicopter is blown up you can see it is the same helicopter that was blown up the first time. The writing on the helicopter is reversed compared to the first helicopter. (00:21:10)
Revealing mistake: When the two FBI agents are thrown out of the car, you can see they are clearly wearing body armour under their clothing just for the purpose of breaking the fall. They look "fat" mainly on their torso because of the padding.
Revealing mistake: When the car at the end flips over, you can see a circular object underneath the vehicle, about the size of a tyre (very obvious in slow motion). This is the device that "lifts" the vehicle for it to flip on one side, timed with the appropriate explosion.