Continuity mistake: When Reid and Kato are fighting by the pool, the beach ball falls off the chair (beside the pool) when they land in the water, but is back up on the chair in a following shot. (01:12:25)
Other mistake: In the pre-credit scenes when the chopper spots the runaway car, Driver guns it (he clenches his jaw, fists and you hear the engine revving and gears changing) but he never catches up with the two cars only a few feet in front of him (which are proceeding at normal speed) for the whole length of the bridge.
Factual error: In the scene straight after the opening credits we are taken to Baker Street where construction work is being done. This work is identified by a sign with a logo as being for the underground line. The logo type face was developed by a Mr. Edward Johnston for London Underground from 1913 but the distinctive typeface used in the film was not in place until 1919. This is obviously long after the 1891 setting of the film.
Plot hole: In the last car-chasing scene, the timekeeper had switched his car to chase them, then how could Justin Timberlake get the timekeeper's salary (a day's time) from a car that the timekeeper picked up from the streets?
Suggested correction: I think it is the car of another time keeper. Hence, it may have a time transfer system.
Factual error: When the bus slams into Brian's car at the start, Brian's car doesn't move an inch. Given the speed and weight of the bus, Brian's car should have been shunted a good distance. (00:01:45)
Continuity mistake: After Slide locks Josh's boss in the master bedroom closet within Mr. Fitzhugh's ex-apartment, he turns on the boombox at a high volume. Then later in the film, when they are retrieving the car through the window of the same apartment, the music is off. Then later, Josh's boss is seen trying to get out of the closet and the music is back on. (01:08:20 - 01:19:55)
Continuity mistake: When Boyle arrives in his police car at the house where McCormick is murdered, he turns off his engine and his windscreen wipers are pointing towards the sky. In the next shot you see the windscreen wipers in their normal position again.
Continuity mistake: The overall timeline of the film is about twelve months but it is inconsistent as far as the seasons. When Blomkvist arrives at the Vanger's island, it is the dead of winter with deep snowfall. A short while later, when Blomkvist is talking to the detective on a pay phone (who asks if he is surviving the winter weather), the snow is gone and the deciduous trees have no leaves, but a few minutes later, when the scene cuts to Henrik Vanger being rushed to the hospital, it is suddenly the middle of summer, sunny and the trees are in full bloom. When Lisbeth arrives on the island, and she and Blomkvist are sitting outside at night talking, the trees close to the house are bare and a howling wind can be heard in the background, but the next day trees have leaves. Some weeks later, when Lisbeth saves Bloomkvist from Martin, it is winter again, with heavy frost on the ground and trees are bare once more. A little while after that, when Lisbeth and Blomkvist go to find Harriet, trees on the street are in full bloom. A day or two later, when Blomkvist is talking to Harriet in the park, it is apparently now early spring because the smaller deciduous trees are only just beginning to sprout new leaves while some bigger ones have none at all. At the very end, it's just before Christmas again.
Factual error: In the scene where Jack Black is kneeling over Shirley MacLaine's body in the garage, you can see the outline of his smart phone in his pocket.
Factual error: In the climax of the movie, Nicholas Cage uses a nail gun like a marksman, hitting with precision the bad guy that holds his wife tight. Besides this skill of his coming out of left field, a nail gun does needs a surface against the opening. It does not shoot nails in the air without pressure being applied, it's a Hollywood trope. (01:18:45)
Continuity mistake: In the scene where Deputy Rose Gammon approaches the car with the body of Cindy Van Alden in it, the position of the car changes between shots. From within the police car, the car with the body is parked diagonally with the rear end in the road. From the long shot, the car is off the road and parallel to it.
Continuity mistake: At the start of the film, when the bus driver helps the man in a wheelchair onto the bus, his hat disappears then reappears. (00:05:00 - 00:06:00)
Factual error: Danny Greene has a bomb placed in Shondor Birns' car. As Birns is waiting to cross the sidewalk, the pedestrian walk-don't walk sign is a modern digital sign, that was not around in 1975.
Visible crew/equipment: During the torture and murder of Troy there is a moment when Jamie, unable to watch the violence, sits in the kitchen with accomplice Mark Haydon. Jamie and Mark sit in silence at the kitchen table and the film cuts between close-ups of them. In the two close-up's of Mark you can see the boom microphone reflected in the glass of the kitchen cabinet near his head. This happens twice and the microphone lingers both times. (01:15:29)
Revealing mistake: When Anna's looking at her reflection in the mirror she starts rubbing her face vigorously. Look at her right cheek and you'll it's red before she rubs, result of multiple takes.
Plot hole: When the hikers heard the voice calling out for help, they were yelling "can anybody hear me" and "is anybody there" in English. Once they rescued her and they tried to talk to her, they said she didn't know any English.
Other mistake: Spoiler alert! At the end, when the sniper shoots the killer, Eve says he is 800 yards away, but within the next 30 seconds he appears at the scene. (01:22:02 - 01:22:32)
Continuity mistake: When Paul is chasing Bozlovski at the port, he repeatedly shoots through his passenger side glass, destroying it. A few seconds later, the glass can be seen undamaged when both cars are banging each other.
Other mistake: At the beginning, the arrival board has the cities listed in alphabetical order, but "San Francisco" comes after "San Jose" when it should come before it.