Revealing mistake: When Chris is trying to escape out of one of the first floor windows, the shots you see from outside are of a stunt double with really bad frizzy hair. (01:14:40)
Revealing mistake: Mac and Dillon go after the Predator. The Predator is sitting in a tree, and Mac points him out to Dillon. They both agree that they see it and take position. Mac crawls underneath the alien and is killed by his laser. The Predator then sees Dillon and lasers his arm off. Dillon's arm falls to the ground with the gun firing. Quickly Dillon turns and reaches for the machine gun around his neck. When he turns you clearly see his bloody right stump and his right arm sticking out the bottom of his jacket. [Note: As far as I can work out, this has been cunningly edited out of the UK DVD version].
Revealing mistake: When Tiffany calls Ruth Bailey, you can see that the mobile phone she uses is turned off.
Revealing mistake: When George Clooney is talking to Juliette Lewis towards the end of the film, it is painfully obvious that his tattoo has been smudged. (01:40:35)
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: After Martin cuts his arm off, there are several scenes where you can see the bulge of the actor's real arm under his jacket. This is most noticeable when he is running through the birch wood, and when rooting through the ruins of the burned cabin.
Revealing mistake: While Cath is trapped on the other side of the fallen boulders, Dan tries to move some of the rocks to get her out. You can see one of the rocks by his feet move as if it is made out of foam. (00:34:25)
Revealing mistake: When the oldest son is being pursued by the unseen entity whilst the family is seeing the priest. You can see a crew member in green pants and brown shoes to the left as the camera perspective turns upside down.
Revealing mistake: When Fin decides to help the kids on the bus and says, "Water's rising, I'm gonna go up to the bridge and rappel down," two shots later the camera zooms in on Fin's car up on the bridge, but the problem is that this shot is shown in reverse - all the vehicles in both lanes are going backwards.
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: After the crazy man cuts his own hand, he laughs and waves the knife. Watch carefully and you can see the hose behind the blade the blood came through. (00:13:40)
Revealing mistake: When the house has been locked down at the beginning of the film no moonlight could come in, however when the guests are being shown the coffin with the guns in there is a shaft of bright moonlight shining on to it.
Revealing mistake: When Erin gets into the truck, in the next shot the camera backs up a little and you can see that it's only raining on the truck.
Revealing mistake: Look closely at the footage when the vampires are entering the cave. Later when they are exiting the cave, the waves are flowing backwards. The same footage has been reversed. (01:17:05)
Revealing mistake: In the beginning of the movie, when Michael removes the knife from the drawer, you can see the blade bend.
Suggested correction: Lol, the knife does not bend at all. The entire knife just moves at an angle as Michael pushes the drawer closed. I paused and slowed it down, looking for the bend.
Revealing mistake: In the hospital scene when the nurse is filling the tub for the patient in the room above the cowboy's, he leaves the water on. When the water starts to come out of the tub it is coming out many times faster than it is going in.
Revealing mistake: In the scene where Ronnie visits Brundlefly for the second time we see Brundlefly walking on the ceiling and wall, however his shirt doesn't remain consistent with gravity. This is especially obvious when he pulls his shirt up to show Ronnie his new tumor and then places it back down. The shirt appears to be being pulled up to towards the sky from Ronnie's perspective. (01:07:30)
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)