Revealing mistake: Just as the bus begins to roll down the mountainside, cables are visible which were holding the bus in place. Most easily seen during the first complete rollover. (00:05:45)
Revealing mistake: The roller coaster used for the Devil's Flight is really the Corkscrew at Playland in Vancouver, where all three movies were filmed. If you look during the opening credits, you can see the name "Corkscrew" up in the lights above the coaster. After this, it says Devil's Flight during the rest of the roller coaster scenes.
Revealing mistake: Near the end, when the captain is walking out of the labyrinth holding the baby, you can tell it's a dummy. The baby does not move in the slightest, you can't even see it breathe.
Revealing mistake: When one twin (presumably Alfred) is removing the other twin's fingers, "Alfred's" upper arm passes through his twin's head as "Alfred" reaches for the hammer. [Fixed on DVD.]
Revealing mistake: After Raye has finished writing down the agent's names onto the piece of paper on the subway, the "dead" man next to him can be seen swallowing. (00:57:30)
Revealing mistake: When Gabriel Noone goes to see "Peter", he arrives in rural Wisconsin, looks out of the window of his car, and sees a mountain in the distance. There are no mountains in Wisconsin.
Revealing mistake: When Vanessa comes out of the girls shower and walks to her locker, in the back shot you can quite clearly make out the strapless bra she is wearing under her towel. Also, when she lifts her arm up you can briefly see the black material under the towel.
Revealing mistake: When Lee is being lifted into the incinerator, he moves his head, despite being dead.
Revealing mistake: When Zoe is getting killed she is spitting out blood from her mouth. Everything is ok with that, except she spits some of the blood on the camera right before she is thrown over the balcony.
Revealing mistake: As Clouseau falls down the stairs when pretending to read the newspaper, you can see his legs flick up after he has supposedly fallen beyond sight - indicating he fell onto a mattress just below the camera's view.
Revealing mistake: When everyone first gets off the bus outside the hotel, Williams shakes hands with Margaret. If you look at his wrist you can see his real skin, not the prosthetic which is supposed to go nearly up to his elbow. It can be seen a little better in the next shot as well.
Revealing mistake: The infant baby was computer animated in every scene in which the face appeared. Even the feet were obviously touched up by computer in the hallway scene. The lighting isn't quite right, the skin texture isn't quite right, and the child's face is just too animated.
Revealing mistake: Uhl talks about Eisenheim's childhood, and about the vanishing tree. Problem is that not only the tree disappears, but also his very own shadow, making him look as if he's floating in a landscape, thus giving away the green screen effect. (00:06:50)
Revealing mistake: When Langdon comments on the geometric pairing of the two pyramids you can tell the point of the crystal pyramid is slightly to the left of the point of the other pyramid.