Continuity mistake: Celeste's white Honda (Alabama plate #LF8VN3D) is riddled with bullets right after she drives up to the cabin, but there aren't any bullet holes later after the police show up. (01:26:00 - 01:45:00)
Continuity mistake: When Eddie Murphy's assistant makes assumptions about why Jack isn't speaking, he throws his notepad down and has empty hands as Jack pushes him out of the office. When the angle changes, he has a notepad in his right hand.
Continuity mistake: In the scene near the end of the movie where Ellen Miller asks Robert Miller to lift up his shirt, and then slaps him in the stomach with a newspaper, we see that his right shoulder suspender is properly positioned, however in the next shot from behind him his suspender over his right shoulder appears to be twisted 180 degrees. As he turns to walk into the inner bedroom the suspender is once again back to a proper fit.
Continuity mistake: When the mean Santa puts the little girl in his lap and asks her what she wants, she's wearing gloves. When it cuts to a different angle, suddenly her gloves are gone.
Other mistake: Aladdin slices off one head of the monster in the tomb. The body spurts copious amounts of blood and the severed head even bounces on him repeatedly, but Aladdin's shirt is immaculate afterwards. (00:04:40)
Factual error: When Dave shoots Justin 8 times, he empties the magazine of his semi-auto handgun, but he continues pulling the trigger, and the gun clicks several times. Semi-auto handguns do not "click" when they are empty, because it's impossible to pull the trigger. Also, the slide of Dave's handgun does not lock in the open position when the magazine is empty, as it should.
Continuity mistake: Alexandre Lagarde puts his fork into the plate of the attractive client, much to the scorn of her husband. The morsel in close-up and the one she actually puts in her mouth are different. (00:06:10)
Other mistake: During the end credits, there's a misspelling. An 's' is missing from 'First Assitant Camera'. (01:33:05)
Continuity mistake: When the mother breaks the window to enter the neighbor's house the next frame shows the glass still intact. (01:07:00)
Continuity mistake: In the parking garage scene, when Lindsay initially parks the sign states "Reserved For Walter Deeds." When being towed his name on the sign disappears. (00:06:30 - 00:10:45)
Continuity mistake: Tom walks into Anthony's memory. Anthony is sitting by the pool next to a table with two glasses of beer, which are 1/3rd empty. A few minutes later the memory is replayed, but this time both beer glasses are mostly full. (00:49:50 - 00:58:35)
Continuity mistake: While he is copulating with Laurence, François Monge receives a phone call from his boss about the murder case in Bobigny. To shush his vocal partner, he gives her a slap on the shoulder, but he does it with the right hand in the view from behind, and the left hand in the full frontal. (00:08:55)
Character mistake: It's said in the movie a vice presidential candidate never gave a concession speech. Geraldine Ferraro did this in 1984.
Plot hole: The killer has been living in the (apparently big enough) crawlspace between walls and floors, for over a decade. There is no explanation (or rationale) given on how he moved the various objects inside every room, closed doors, fed when the house was not occupied, hid the various corpses and, silly detail, concealed his own BO and the stench of his own living quarters, which is something hinted at when they find out his hideout. It is explicitly said that he is agoraphobic and does not get out, ever.
Revealing mistake: Lazy prop department at work in the opening credits of this movie; look at the guest list. The second page and the first page are an exact copy and paste of the same names and addresses. (00:01:35)
Continuity mistake: When Jeremy and the cop girl are shooting for practice, the amount of cans changes between shots.
Continuity mistake: In the intro, the mother is playing with her kid; notice that when she grabs the gladiator puppet she is holding it with the index finger above the shoulder in the wider angle, below in the frontal close-up. (00:01:00)
Factual error: The Life One spacecraft is hit by a micrometeoroid. Sparks are to fly, among other effects. The sparks are bifurcated, meaning they were produced by using a grinder, not by a micrometeoroid collision.
Continuity mistake: Dinner at Forestier's home, and Georges Duroy does not know which knife to use to eat. The asparagi in his plate are across the small pie in the wide shot, and in close-up they are arranged entirely on the side without his intervention. (00:08:20)
Visible crew/equipment: When the 2 bad guys get the car you can see the 2 cameramen reflected in the car door. (01:10:00)