Factual error: When Yuri's daughter is getting away from the hotel tower, she has to walk to the next building located in front of the tower's window to take the chopper. It should take several minutes, but she does it in a few seconds. (00:48:25)
Other mistake: When John and Jack are in the ball room, the chopper circles back and begins shooting through the building at them. It is shooting into the far right window straight forward. John and Jack get up and take off running. As they do, you can see the bullets' line of fire moving with them through the building as the chopper tries to hit them. But it cuts to an outside view and the chopper has not moved or turned yet from that spot, nor are the guns turning. It is visibly still shooting forward at the same spot. The line of fire follows Jack and John some more, but the outside view shows the chopper just then start moving to begin following their movement. (00:52:40)
Continuity mistake: Just after John asks Jack if he is "gonna cry a little" before he pulls the bolt out of him, Jack leans his head back. The next shot, Jack's head is down. Throughout this scene, his head keeps changing position between shots. Also noticable right after John says "You shot?" (00:58:25)
Audio problem: When John pulls the iron rod out of Jack's abs, he throws it on the floor. It is the size of a large bolt, but the sound it makes is the sound of a large iron pipe. [Fixed on Blu-ray]. (00:59:05)
Continuity mistake: When John and Jack are discussing if he meant Chernobyl, the blood on Jack's face disappears instantly. (01:00:50)
Visible crew/equipment: When walking into the vault at Chernobyl, a cameraman is reflected in one guy's gas mask visor. (01:02:05)
Plot hole: When John has Yuri pinned to the uranium boxes, Yuri reaches into his coat and turns on his walkie talkie so his daughter and minions can hear. John McClane doesn't notice and he is right there. There are two things wrong with this. We hear the beep the radio makes when it is turned on, and it was loud enough that John and Jack would have easily noticed. But even if they didn't hear it, there is another issue. John is a New York cop, or even a detective. As such, he would have extensive training for dealing with armed men, and he would have noticed Yuri reaching into his coat. Even if he didn't hear the radio beep, he would have stopped Yuri's hand or done something, assuming Yuri was reaching for a gun. (01:18:15)
Factual error: It is not plausible that the tail rotor blade of the helicopter can destroy large parts of a building without being damaged. (01:24:40)
Continuity mistake: At the end, Jack and John fall into the pond and get soaked. As they walk out of the building their clothes are completely dry. (01:29:15)
Continuity mistake: At the end, the wreckage of the helicopter changes position instantly. Note the position where the rotor blades are. In one shot they are on the side, then on top. (01:29:35)
Continuity mistake: In the scene when Yuri's daughter is getting away from the hotel, the color of the chopper changes from green to brown between shots.
Continuity mistake: Throughout the blue van chase, the damage to the van is constantly changing/repairing itself.
Continuity mistake: During the chase with the blue van, it keeps changing model. Starts with a van with high roof, than low roof, high roof again. And this goes on and on.
Plot hole: When Jack and John are on their knees in the hotel, with their hands zip-tied behind, Jack manages to use a hidden knife to cut his bindings and starts kicking bad guy butt. Jack immediately joins the fray but a careful review shows that at no point did John use his knife to free Jack.
Continuity mistake: During the opening chase the chase goes along the river from left to right as you look at the screen. They make a turn and now go from right to left as you look at the screen, along the same river.
Revealing mistake: When the armoured truck hits the first parked car you can see the smoke appear at the side of the car and a jet of smoke when it flips from the air cannon.
Revealing mistake: In the opening chase with the armoured truck it comes up behind a blue car that is already dented on the near side, which is the side it slides round to so the truck hits it. It then gets pushed onto a silver van that is completely wrecked from previous takes.
Factual error: The nuclear power plant at Chernobyl is located 4 km from the town of Pripyat, which is located in a forested area, and the plant is not visible from the town - in this movie it's clearly in visual range.
Continuity mistake: When John is in the taxi in Moscow, there is one shot of the taxi with a sticker in a bottom corner which disappears.
Continuity mistake: When arriving in Chernobyl from Moscow it seems to be the same night, although it is over 800km, plus their car is bright and shiny when they arrive despite driving through the rain.
Answer: His name was Anton. He was an associate of Viktor Chagarin. Jack, although lying, said Yuri Komarov sends his regards. Chagarin and Komarov were former partners and Chagarin was the one who got Komarov put in jail. By Jack saying Komarov sent him, it made it seem like Komarov was out for revenge on Chagarin (by attacking his associates). The courts offered to reduce Jack's sentence for testifying against Komarov, which allowed Jack to get close to him and help him escape.
Bishop73