Continuity mistake: When the elevator free falls and the floor opens, all the shots from below, with or without the woman falling through the hole, show the elevator is empty. (00:13:50 - 00:13:55)
Continuity mistake: Shortly before the bus gap you can see an END sign at the end of the road. This disappears a second later. (01:03:11 - 01:03:36)
Continuity mistake: When Jack tells the other cop to "turn it on" in reference to the money tracker, soon as they realize Payne has the money, and Jack runs out to the garbage can, the red car that screeches to a stop to avoid hitting him is a red Ford Tempo. In the very next shot from the opposite direction, it's a red Mazda Protege. (01:36:55)
Continuity mistake: When McMahon is in a helicopter trying to guide the bus from downtown traffic onto a vacant freeway, the bus passes through the same neighborhood twice from one overhead shot to the next, roughly one minute later (pay attention to the recurring trio of flagpoles on the right, as well as a pair of cars that the bus overtakes). (00:48:55 - 00:49:45)
Continuity mistake: When Jack is inspecting the bomb from a red trolley connected to a tow truck, a spool of cable unwinds and breaks free from its clamp, leaving Jack to fend for himself. Soon, McMahon and Norwood are riding alongside the bus trying to see if Jack is okay, but notice how the cable has reattached itself to the empty spool. (01:16:30 - 01:17:30)
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Continuity mistake: The 2 SWAT team members are not visible on the preceding truck between two shots. (01:12:55 - 01:13:32)
Continuity mistake: Right after the bus jumps the gap, Jack hugs Ortiz. Immediately following you can see the reflection of the stairwell at the front in the mirror. The stairwell and door are both fine, after having been blown off when Helen died. (01:07:00)
Continuity mistake: As Annie shouts at Sam and suggests he drive over the line of cars up ahead, the bus passes by a couple of bridges - visible through the side window where she and Helen are seated. But no bridges were visible anywhere at all when Sam first noticed the endless line of gridlocked traffic just seconds before. (00:33:55)
Continuity mistake: Jeff Daniels' character gets shot in the thigh by his partner. Later, when he gets his award, it is the opposite leg that has a cast on it.
Continuity mistake: At the very start of the movie, in the basement, you see a security officer walk past some numbered steel pillars, he walks past the pillars numbered "15" twice. Fixed in the Blu-Ray. (00:03:35)
Continuity mistake: When Jack is chasing the bus on the freeway in the Jaguar, an overhead shot is shown of the bus with three cars around it, but in the next shot of the traffic, the road is full of traffic which is surrounding the bus, which is highlighted by Jack having to swerve around the cars.
Continuity mistake: In the scene where Jack is fighting Dennis Hopper on the roof of the subway train we see Jack lying on the top of the train getting punched by Dennis. We briefly cut away, and then back to Jack and the corrugations on the train roof have rotated through ninety degrees.
Continuity mistake: In the scene where the plane is blown up at LAX, the intact plane is shown with no mountains in the background. However, the scene showing an exploding plane has a backdrop of desert mountains, presumably Antelope Valley California.
Continuity mistake: When Dennis Hopper's shooting the shotgun through the lift roof, the number of holes doesn't match the number of blasts. He shoots once and a hole appears. We then see a close up of him and he shoots twice more, but when we cut to the ceiling after the third shot overall, there are only two holes in it. Doesn't seem likely he'd miss the roof at a range of 2 feet. (00:18:55)
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Continuity mistake: After Jack shoots Harry in the leg, Denis Hopper runs out the door which is wide open. The explosion shot (seconds later) happens and we see the door completely shut. (00:22:05)
Continuity mistake: After the bus has left the freeway and enters the city for the first time, there is a scene where Annie is driving the wrong way down a street and Jack can be seen standing right next to her. She pulls the bus onto the right side of the road and Jack puts the cell phone to his ear. In the next shot, he repeats the same action.
Continuity mistake: In the scene where Jack drives the car backwards so he can tear off the door, enabling him into the bus, he slams into a silver car. The very next shot, maybe two seconds later, there is another car driving behind him like nothing happened. (00:39:15)
Continuity mistake: When Jack is running across the street in downtown Los Angeles, in two different camera shots two different red cars are shown stopped in the same place to let him cross the street.
Continuity mistake: When Jack and Harry are pulling people out of the elevator there are two men offering to help the stubborn lady out of the elevator. 2 seconds later there is only one man jumping to get out. (00:15:50)
Continuity mistake: When Keanu Reeves is on the payphone with Dennis Hopper, his lips appear increasingly redder throughout the scene. (00:28:00)