Continuity mistake: Once the tow truck is attached by cable to the HK, it is spun around. As the truck's rear end is approaching the Honda Element, we can see Kyle making his way into the cab for protection. But a quick external shot of the rear of the tow truck shows Kyle is behind the cab, holding onto the exhaust stack. Then a high shot showing the Honda get hit shows Kyle is gone, apparently safe inside the cab. (00:43:15)
Continuity mistake: When Marcus hits the side of the compartment that contains Kyle and Star with an axe for the second time, we see the panel's left edge separate from the vertical column, bent in a large "V" inward into the compartment. The next exterior shot as Marcus is grabbed by the harvester shows the panel has only the one small hole in it that Marcus created with his first axe strike. The damage from the second hit is gone. (00:44:15)
Continuity mistake: This is near the end of the tow truck chase scene. Just when the truck hits the railing and Kyle and Star are thrown from the truck, Kyle is caught in the right hand, Star is caught in the left hand. But when the shot is coming from inside the transporter, Kyle is dropped from the left hand and Star is dropped from the right hand. (00:44:20)
Continuity mistake: When Williams is hung up by her parachute after ejecting, Marcus climbs the structure next to her. She asks for her knife and with her right hand begins to cut herself loose. Once she cuts through, she immediately begins to drop of course, but Marcus is able to catch her in mid-air by her right hand. Suddenly the knife is gone. There's no way that in the split second between cutting through the strap and Marcus catching her in mid-air she would have had time to release the knife. (00:47:00)
Continuity mistake: In the scene where Marcus finds Blair hanging from the power tower, it shows a dark tan stripe around her eyes, but in the following shots it is much lighter and less dark than the previous seconds. (00:47:00 - 00:48:00)
Continuity mistake: When Marcus was freed by Blair and they are trying to escape through the shaft, Barnes shoots a rocket at them. Marcus lies on top of Blair as the fire goes through the shaft, but you can see that Blair's hair is sticking out from under Marcus. When they get up, Blair's hair is not burnt at all. (01:06:40)
Continuity mistake: In the scene where Blair escapes with Marcus and Barnes launches an explosive into the tunnel, Marcus hops onto Blair to save her from the scorching flames. After the fire, Marcus' coat would have been burnt to a crisp, his hair singed off and the skin on his back fried. More evidence pointing to this was that his coat was merely one previously worn by a Resistance fighter, not special in any way, and he has regular skin and hair. (01:06:50)
Continuity mistake: John Connor, whilst battling the T-800, fires a shot into a wall to create an opening. Star jumps through the hole to the left, Kyle jumps to the right, and John jumps through the centre, yet in the next shot Kyle has landed in the centre and John has landed on the right. (01:27:35)
Other mistake: A spelling mistake in the credits lists Diego Lopez as a "soilder" instead of the intended soldier. (01:27:45)
Revealing mistake: After Marcus rips out his chip implant, he picks up a steel stool and throws it through the screen. The stool stops in midair as soon as it breaks the screen, which is a mistake in itself. The stool does so because there are wires connected to the stool, at least one of which is visible: a microfilament wire from which the stool is suspended. It is attached to the the stool at the pole between the upper and lower plates. The displays on the other computer monitors in the background appear to have been meant to help disguise this, but one line in particular moves in perfect sync with the stool. Also, the wire snaps taut, then wiggles with slack, whereas the lines on the monitors remain completely straight at all times. A previous correction claims that no wire is visible, but that is completely erroneous. (01:30:00)
Continuity mistake: Just after Marcus rips out his chip and throws the stool, he jumps to the lower level. As he walks up to the resistance soldier on the MRI table, if you look at the top edge of the screen, you can see that the awning is all damaged from being shot by the terminator that Kyle stabs in the neck. However, the scene where this occurs happens about a minute after Marcus jumps to the lower level. (01:32:55)
Continuity mistake: When John Connor is carried to the helicopter, we can see the older lady Virginia in the helicopter. After the helicopter becomes airborne, Virginia is not seen again. (01:41:10 - 01:41:50)
Continuity mistake: This is right after Conner jumps down to the lower level to get to the grenade launcher and hurts his shoulder. He is crawling away from the T-800 and the shot is from right behind Conner's head. The T-800 is practically right on top of John, but when he shoots the oven and the molten steel lands on the T-800, the shot shows John like 30 feet away. (01:41:15)
Revealing mistake: When Barnes and Marcus Wright are helping John Connor back to the chopper and when Barnes gets in the helicopter, he's revealed to be a stand in. It's in plain sight, at the right side of the screen. (01:41:20)
Factual error: In the scene in the 'cattle car' the shadow and light from outside the bars is moving across Kyle's face as he is talking. But unless the light source moves relative to the shadow source, a shadow will not move. But the light source was just outside daylight - and not direct sunlight - so the shadow inside would not have moved.
Factual error: Throughout the movie, it is established that it is set around Southern California. However there are many natural landmarks shown that are hundreds of miles outside of California such as the Rio Grande Jorge, the Sandia and Manzano Mountains, all located in New Mexico.
Continuity mistake: At the start Connor jumps in a helicopter and takes off, at which point it gets shot down. When it crashes upside down he undoes the lap belt and falls out of the seat, problem is he never did the belt up in the first place and he was wrestling with the controls, so he couldn't do it up when crashing.
Revealing mistake: When the tow truck is dragging the bike, as it goes onto the bridge the drag line is visible in the mud from previous takes.
Continuity mistake: While John Connor is above the small lake in a helicopter searching for Marcus, he and his crew are attacked by snake-like robotic arms that rise up from the water. The arms partially penetrate the cockpit but in brief, subsequent shots of chopper, the arms, which should be extending from the exterior, are nowhere to be seen.
Revealing mistake: In the final scene when Marcus get John in the helicopter he is wearing a glove with markers where his metal hand should be.
Chosen answer: It was a strike by Skynet on the attacked facility to try and deny the resistance information and anything useful.
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