Revealing mistake: In the scene where Ashley is brought back wounded from the raid where Scarlett's husband Mr Kennedy was killed, Melanie grabs an oil lamp to follow the man carrying Ashley to the bedroom and you can see an electrical cord hanging down from it.
Picture edited by Super Grover
Continuity mistake: After Gerry gets smacked in the face by the 'broken' suspender clasp, we see the silver clasp land under the dresser. Yet, when he's moaning and lifting his leg to get onto the bed, we can actually see the clasp still intact on the front suspender that came loose, which is dangling right behind him (just look between his legs). Of course, in the next shot, that clasp is gone. Since the silver clasp is one of the plot points, this is bizarre to say the least.
Continuity mistake: When John and Catherine are in the hangar at the runway, the Cessna's tail number is N3035C. When the plane is shown in the air, the number is N3973F. When they land, the tail number has changed back to N3035C.
Continuity mistake: In the bedroom scene the girl is holding a clear cup full of beer. The camera goes off her and when it comes back she is holding a blue cup. The camera goes back off her then on her and the cup is clear again.
Continuity mistake: When Sam is in his bedroom, after he finds the Cube sliver it falls and dramatically burns a hole through the floor into the kitchen. But Sam's bedroom is over the living room (there is nothing on the ground floor below Sam's elevated bathroom, and in the first movie Jazz hides in this open space), and the kitchen is actually located between the den and dining room, at the other end of the house. If they were to follow the actual floor plan of the house, the Cube sliver would have landed in the area of the piano in the living room, but where would the fun have been in that?
New this month Continuity mistake: When Stuart is leaving the building, he enters a previous generation Mercedes Benz S Class. The next couple of shots where he is being followed by Bryan shows the newly redesigned S Class.
Continuity mistake: Agatha's nightgown strap switches between hanging down on her arm, or being up on her shoulder, normally.
Factual error: When Koba steals an Armored Security Vehicle class M1117A Guardian, he kills the gunner from the turret and then somehow manages to use the 240B attached to the turret. First, it takes three men/apes to operate the ASV, and second, the ASV cannot be operated from the turret. In that scene, it is assumed that Koba is operating the entire vehicle, something most humans cannot do or do not know how to do. Let alone a 240B, MK19, or .50 Cal M2 Browning. The ASV turned in the direction of the wall, which was the only way that the Apes were able to breach the city walls. This is also kind of an important plot hole blunder too because if it were not for the breach from the ASV, the Apes would not have won. The other blunder from this is that the gunner would not have been exposed from the hatch, since the ASV was using .50Cal and MK19. No need to use the 240B.
Continuity mistake: Fairly early in the movie, Margo comes to see Nick, who is upstairs in a bedroom. The press is outside clamoring, and Margo locks the deadbolt on the front door. After her talk with Nick, she's in a hurry, rushes downstairs and opens the door without unlocking the deadbolt.