Revealing mistake: During the four-year flashback scene in East Africa, after the building is bombed, two helicopters fly to the right of the building. However, because they are CGI, the telltale whirl (or any movement) the blades should have made in the smoke isn't there. (00:50:10)
Revealing mistake: The close-up shot in which SnakeEyes shoots at the roof of the Hummer is flipped, the ejection port is on the wrong side of the gun. And yes, it is a real gun, not one specially made for this film. (00:57:30)
Revealing mistake: When SnakeEyes is hanging from underneath the Hummer, the same shot of him turning his head is used twice: the first time just before Scarlett blows the head off of the guy who the Baroness orders to kill SnakeEyes, and the second time just before the train hits the Hummer. (00:58:10 - 01:00:20)
Revealing mistake: In the scenes at the base on the surface of the ice, the breath of the actors is visibly CGI and not natural. (01:13:30)
Revealing mistake: The clarity of the water in the Arctic scenes would not allow anyone to see the underground base from as far away as it was seen throughout various points in the movie. (01:14:45)
Revealing mistake: Around 40 minutes in the movie during the fight scene, a Humvee gets hit by 3 bullets (2 in the second door, 1 behind the door). Besides looking very fake, the bullet holes seem to have dissapeared when the Humvee is blown away a few seconds later.
Revealing mistake: When Storm Shadow is stabbed at the end of his fight with Snake Eyes, watch closely as he pulls the blade out before falling. You can see that he has two slices/cuts on his right shoulder. The cut on top is a rather realistic-looking prosthetic, but the cut underneath looks incredibly fake. It's just regular red and purple makeup that was "drawn on" to his shoulder in the shape of a cut and touched up with a small amount of fake-blood. It stands out against all of the other cuts, which are are convincing prosthetic "cuts."
Answer: He was seeing some of the first footage of experiments with the Nanobots by Dr. Mindbender. And the whole plot of the movie is about him using them weaponized and for replacing the president.
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