Deliberate mistake: Leaven spends too much time thinking about if 645 and 372 are prime numbers to be believable. But she knows the factors of 649 and the result of 26 to the power of 3 almost immediately. Plus anyone with any maths knowledge whatsoever would know that any even number (or one divisible by 5) can't be prime, so 645 and 372 could be dismissed without even thinking about it.
Continuity mistake: After Barry has jumped into the water reclaim the crown, he comes out of the water with a perfectly clean shirt but in the next shot the blood is back on his shirt as expected. (00:22:50)
Visible crew/equipment: If you look really close in the background as the killer throws Cici off the balcony, you can see someone sitting in a tree, wearing black, with a camera. (00:33:35)
Revealing mistake: When the body of Miss Lefferts is being viewed, the 'dead' girl blinks slightly. (00:34:35)
Continuity mistake: In many places in the movie, a cat noise is heard even though the cat's mouth is quite obviously not open or the cat is licking its face.
Plot hole: In the scene where Ashley Judd runs away from her attacker and falls into her aquarium he has moved to the bottom of the stairs - there is no way he would have been able to move that full fish tank. It looked to be about a 30 gallon tank - it would weigh about 400 pounds with the stand and even if he slid it with some superhuman strength, glass tanks are notorious for shattering when you move them full. Plus it would've made enough noise to wake the dead - no way she wouldn't have heard it.
Plot hole: When Nick confronts the P.I. and yells "Why are you following me?", he looks inside the car and see the file with his picture on the front seat. The P.I. notices this and turns the file over. After Nick grabs his gun, the P.I. jumps out on the other side, raises his hands in the air and tells him someone hired him and runs off. As the P.I. runs off, Nick yells "Who hired you?" as he stands alone next to the car. He then waits a minute and walks off. If he really wanted to know more information, he could have taken the file that was right in front of him on the carseat. It makes no sense that he is desperate for information about the strange events that are going on, sees this file on him, and yet doesn't even pick it up or look at it. (00:59:55)
Continuity mistake: When the Lady Chablis "crashes" the debutante ball - she leaves her purse on the table while she dances, and then forgets to retrieve it before she leaves. (01:44:35 - 02:07:50)
Other mistake: When the slaves are getting into the Portuguese ship (the "Tecora"), the crew shouts in clear Spanish (some Spaniard and some Mexican accent) rather than the expected Portuguese. (01:18:10)
Continuity mistake: Towards the end of the movie, when all three are crawling through the Lincoln Tunnel, they are almost waist deep in water. Yet, the Secret Service lady's jeans change from dry to wet and back again. The same when she is chased back through the tunnel, her and the Secret Service guy's trousers are dry.Christoph Galuschka
Continuity mistake: When Jerry is on the bus with Alice, one second he's wearing his hat, he takes it off, then the next second it's back on, then it disappears for the rest of the scene.
Continuity mistake: When Mr. Eddie goes back to his Mercedes after beating up the "tailgate guy", the left side of the bumper on the Mercedes is damaged. When they drive back into the garage, we see the left side of the bumper is fine.
Continuity mistake: Throughout the entire movie the size of the Event Horizon's interior versus that of its exterior is repeatedly off. Evidence of this is seen mostly with scenes that take place in the main access corridor. First off, it is made to seem that the ship has one central connecting tube, but in the exterior shots there are several tubes that make up the middle of the ship. This is pointed out when Miller is making his way across the ship to get to the air lock that Justin is about to open. Second, the length of the tube (heck even the whole ship) is too small in relation to how the ship appears from the outside. This is pointed out in a few different places in the movie - when the crew is up on bridge, then race all the way to the airlock in the middle of the main access corridor, where Justin has just closed the inner door and when the doctor is asked to go grab his med kit from medical, which is across the ship and he is gone only a few seconds, and also when Miller is running though the corridor to activate the explosive charges. Since the ship has no faster means of transportation, such as turbolifts or a tram system, they could not be covering the distance they appear to be covering in the movie.
Continuity mistake: When Danielle is in the evening gown section in the Miss Madison competition, her dress changes from sky blue to sparkly dark blue after the shot cuts to her mother.
Revealing mistake: After the accident Frank is climbing the hill towards the train. There are several paths of footprints through the fresh snow. One to the left and another up the path he is climbing.
Continuity mistake: When Joe realises that Jimmy isn't turning up at the park he goes to a pay phone, puts the red notebook down with the spine faceing to the right and starting phoning the FBI. In the next shot the the notebook has rotated 90 degrees with the spine now facing the wall. (01:06:45)jle