Continuity mistake: Near the end of the film FBI operatives rappel down from helicopters for speed and immediately enter the warehouse where John McClane and friends are. Almost immediately Bowman appears and vouches for the three left alive in the building. He got there very quickly considering his helicopter was still in the air when the operatives were landing.
Continuity mistake: McClane's head wounds move around throughout the movie. Especially the two red spots on the left side of his head change colour a lot.
Continuity mistake: During the final truck chase through Baltimore, several traffic lights are seen with lights in them. But all the power was off.
Continuity mistake: During the shootout at Matt's apartment John scrambles away from the refrigerator and pulls himself around the corner. The view is from behind John and his chest is facing the corner as he pulls himself around it. The scene jumps to a view from in front of John, yet he's somehow already turned himself around so his back is to the corner (this makes for an easier transition to using the corner as cover, but it messes up the continuity). He couldn't have done this since he was still in the process of pulling himself around the corner.
Continuity mistake: In the scene after the power plant explodes and Farrell is giving his "What is the point?" speech, his hair changes several times between shots, from hanging down in front of his face to being swept to one side.
Continuity mistake: In one scene we see the map of the power grid of Eastern Sector shutting down. All sectors are red. A few scenes later we are in Warlock's basement. He has the same map on one of his screens, but there some sectors are red and some are green.
Continuity mistake: When John and Matt are in the patrol cars and Gabriel has them rerouted to a blocked road, there are no cars on the road besides the patrol cars, but throughout the scene when the camera cuts you can see traffic moving smoothly along with them.
Continuity mistake: During the final chase, the right front tire of the Freight liner is flat at one point after hitting a number of parked vehicles. The next shot showing the front of the truck shows the tire is fine.
Continuity mistake: The hacker slaps McClane's daughter moving her head to the right, hair messy around her face. The immediate angle from the hacker's point of view shows her head tilted to the opposite direction, with her hair perfectly brushed.
Continuity mistake: In the semi chase scene when Bruce takes control of the truck he initially shoots twice through the door and you see two 'bullet holes'. When the cut to the cab the driver is shot 5 more times. After Bruce throws out the driver and closes the door you only see the two original 'bullet holes'. There should be about seven of them.
Continuity mistake: As McClane is powering up the helicopter to fly to Warlock, the rotors are already up at full speed. The next cut shows the helicopter in full from outside with the rotors turning much too slow compared to the previous and following scene.
Continuity mistake: When being escorted by the FBI near the beginning, they are in an FBI car which is plain white. They then get shot at by the helicopter and are seen speeding away in the FBI car. A few shots later this car becomes a normal police squad car.
Continuity mistake: In the next-to-last shot of the movie you can see giant letters SOU on the warehouse behind Bruce Willis sitting in the ambulance. In the final wide-out shot of the movie the same warehouse has no lettering.
Continuity mistake: In the scene where the semi driven by McClane is chased by the F35, the semi hits multiple vehicles causing it to damage. The driver side headlights are smashed and the bumber and fender are almost scraping the ground. In the next shot, headlights, bumber and fender are fine.
Continuity mistake: While McClane is taking control of the Freight liner during the final chase, he jumps onto the driver's steps, and we see the driver's side window is closed, he shoots the driver and whips the door open, and the window is now open. He climbs into the truck and slams the door, and the window is once again closed. There was obviously no time for the window to be opened and closed during the fight.
Continuity mistake: At the very end when McClane is talking to Farrell, he has three steri-strips over his left eye, but when he goes back to his daughter he only has two.
Continuity mistake: At the end when McClane shoots through himself to kill the bad guy, it's though his right shoulder into the bad guy's right shoulder. The next shot of the dead bad guy has the wound in his left shoulder.
Continuity mistake: John M is driving to the Eastern electricity station and chatting. The view out of his window shows him driving past the same distant hill at least three times. Also the speed is faster out of the passenger's side than the driver's.
Continuity mistake: McClane's shoulder holster disappears while fighting in the hanging truck in the elevator shaft. We can see he has the holster again (albeit a different kind) before the fight with the parkour guy.
Continuity mistake: In the beginning once McClane and Matthew have escaped the apartment, and are going through the alleyway, when John gets in the car and throws it in reverse look to the left of the screen. The back driver's side window is rolled down about 2-3 inches. The remaining camera shots during the escape show the window being rolled all the way up.
Suggested correction: Not really a mistake seeing the same hill 3 times. Also the speed can alter quite easily. Not a mistake.
Ssiscool ★
Also, the road could be curving slightly, changing the angle of view with the camera change.