Continuity mistake: Throughout the entire film the tattoo on George Clooney's neck moves position and changes shape.
Visible crew/equipment: At the end when Sidney's dad falls out of the closet, if you look closely you can see the hands of a crewmember who was in there too, pushing items out after him. (01:42:40)
Factual error: The actual Tsavo lions responsible for the killings had no manes - see for yourself; they are on display at the Field Museum in Chicago. [The filmmakers employed artistic license in using maned lions. They were also certain to include - at the very end of the movie - footage of the real Tsavo man eaters, as they appear in the Field Museum.]
Continuity mistake: Before Bonnie's operation to remove her scars they can be seen across her back and down one arm, yet in at least two scenes before the operation she is seen wearing sleeveless or very short sleeved tops with no scars visible.
Continuity mistake: When William Petersen is on a cordless phone at work, he says "the guy gives me the creeps and the girl is my daughter." As he does, the phone cord appears, and the phone's position changes as he hangs it up.
Visible crew/equipment: Outside the chapel, when Frank backs into the pedestal the statue begins to topple over. In the shot facing up, as the pedestal falls and Frank puts his arms out to catch the statue, the wires used in this stunt are perfectly visible. (01:35:05)
Continuity mistake: In the scene where the Graboid is pulling the truck you can see that there is a gun rack and a gun in it. Right before they are about to hit the rock you can see that the gun falls off of the gun rack. The gun goes on and off the rack between the following shots. (00:30:25)
Continuity mistake: Montgomery's shirt, when he is ripping pages out of a book, is blue. However, when Azazello takes the gun from his hunting vest, his shirt is white.
Other mistake: Just as the gang are off to pick the plants they need Faith goes off to talk to Daniel. While she's there the others woop and laugh, but they do it once and it's recorded. It's played 3 more times, straight after each other. Sounds slightly stupid.
Continuity mistake: When Jessica confronts Dr. Fenistone in the doorway, which shoulder her ponytail hangs over changes between shots through the scene. (00:55:55)
Continuity mistake: The terrorist blow up many Jeeps when they ambush the military in the opening scenes. The problem is, they blow up more Jeeps than are in the convoy. When the terrorists steal the truck that was being escorted by the military convoy, we can see there were 3 Jeeps. But during the ambush scene, there are a lot more than that blown up by terrorists using weapons.
Continuity mistake: At the very end there is a shot of (Dennis Miller) opening the door of a car for the lady, then cuts to the inside of the car, where her door is slammed shut, obviously by Dennis Miller, and approximately half a second after her door is shut, the passenger door opens and Dennis gets in the car. He must be able to leap over cars in a single bound.
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.
Plot hole: When Peyton/Darkman is showing Bridget how the liquid skin works, he drips a small amount onto his burnt finger, and it solidifies. However, when he drops it onto his finger, it magically shapes itself into a replica of a perfect, undamaged finger. This makes no sense, as it is simply a liquid and is not being molded by any forces. Hence, it should not look like a perfect finger.
Factual error: The geography throughout the film is all wrong. The setting is in Pennsylvania, near Pittsburgh. The driving times between there and Williamsport are extremely under-estimated. Most egregious is the river structure. The body is found in the river near Sunbury. Not possible from a site in Western PA. Basically all relationships between actual towns/cities mentioned are totally wrong.
Continuity mistake: Before Halleck eats the cursed pie, a fork appears next to the pie between shots.
Other mistake: Janet had a revolver that can fire six bullets but, when she fires it at the werewolf, she fires eight bullets.
Revealing mistake: When the Leprechaun gets sucked into space, he grabs onto the edges of the cargo bay's doors. You can see pieces of his hands disappear into the doors, showing that it's CG.