Continuity mistake: When Jackson comes to pick his kids up to go camping, he is shown passing by the back side of his limo and the trunk is fully opened, but in the next shot the trunk is still opening. (00:14:20)
Continuity mistake: When Jackson and the kids are at the dried up lake in Yellowstone park, they walk past the carcass of an elk. We change to the long shot, and when the army arrives, the carcass has gone. (00:21:35 - 00:22:05)
Continuity mistake: As Jackson is dropping his kids off in the limo, it shows all the mosquito bites on their faces. Later that morning, as the family is sitting down at breakfast, the bites have disappeared and don't show up again.
Continuity mistake: As the heads of state decide to open the gates, we see the countdown timer in the background go from 14:40 remaining to 14:39. We cut to a different angle, and it's back up to 14:41.
Continuity mistake: When the decision to open the gates to let everyone in is made, the countdown is at 15 minutes. When the gate is fully lowered and people start running in, the timer is at 4 minutes. How can they get all the thousands of people on and raise the gates in 4 minutes? It took 11 minutes to go down and 30 seconds to get back up.
Continuity mistake: Nima says that Tenzin will meet them at the West Gate of Cho Ming valley, but a sign at the gate says it is the East Gate.
Continuity mistake: When the RV camper van lands after its jump on the runway, you can see the steering gear and passenger front wheel has collapsed. In the next shot when Jackson enters the camper to retrieve the map, you can see the wheel is fine, and then its damaged again in the next long shot.
Continuity mistake: While Carl is reading the note, a waitress passes behind Adrian. Half a second later she's 3 meters behind repeating the movement.
Continuity mistake: When Jackson picks up his kids to go camping, we see nothing on the sidewalk grass field in front of their house. But when he returns home to drop the kids off, we now see that there is actually a pedestal displaying the address of the house, we can also see this pedestal when the earthquake hits.
Continuity mistake: Right before the scene where the earthquake happens at the supermarket, we see the crack moving through the parking lot. The cars are parked parallel to the store. We see car after car shake, etc, until it gets close to the front door of the store. After the earthquake, when the news is on the TV, it shows the store after the crack has gone all the way through. The parking spaces and cars are facing a completely different direction.
Continuity mistake: When the door opens on the ark to let the mass of people in, there is a large yellow arm that starts to close in on Jackson and his family. The tunnel that his son is pushed into last minute had a large metal door open on it that instantly disappears like it was never there when the arm passes the opening.
Chosen answer: Its a safety device so the ship doesn't put to sea and ends up flooding the ship. The passenger ferry Herald of Free Enterprise capsized in the port of Zebrugge in 1987, precisely because the doors were not shut properly.
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