Revealing mistake: In the POV shot from Thomas, capturing Bill and Ben puffing away from the water tower, Thomas seems to be off-centered from the tracks, making it seem like he is derailed.
Revealing mistake: In the scene were Viago is showing the locket that his girlfriend, Katherine, gave him, he puts it on, and since it's silver, it starts to burn his skin. The smoke from his burning flesh is coming from something on the table in front of him, not from inside his shirt.
Revealing mistake: When James is getting on the St. Charles street car at Carondelet it's raining, but on the north side of Canal St, people are walking in shorts and with no umbrellas.
Revealing mistake: Jim parts his hair on the left side. The stacks of his books on display in the hallway include a photo of him with his hair parted on the right side, but otherwise looking the same. Hair that is persistently parted on one side will not easily part on the other side and lay across the head in the same way. (The image was reversed). (00:25:20)
Revealing mistake: About seven minutes in, during the scene where we see Cooper helping the Nerd as a cameraman, you can tell that Cooper has been added to the scene using green-screen effects, as the actor was unavailable to shoot at the location. The lighting on Cooper doesn't quite match the lighting of the scene, and you can see a slight "blur/feathering effect" around him where the greenscreen background was removed.
Revealing mistake: During the battle of Dale, Bard confronts Alfrid, who is dressed as a woman and is trying to escape with looted gold. During the confrontation a troll climbs over the parapet and is killed by Bard. As the troll falls, Alfrid also falls. When he lands, the ground near his hand ripples like fabric covered in sand.
Revealing mistake: In the beginning of the storm, a trashcan is blown down the street, by the wind. Most of the leaves, lying in the road, are not moving though. (01:28:05)
Revealing mistake: In the news reel detailing the Kohinoor theft, a few headlines appear, and at least one persists on screen long enough to easily spot the inconsistency between headline and article (filler text presenting a new local magazine from the London district of Lambeth). (00:09:00)
Revealing mistake: As Glenn, Blake and Monica are being surrounded by zombies, as Monica asks "Fucking hell, how many more of these are there?", in the background you can see a zombie sitting astride his victim, flailing away with a hammer or hatchet. It is obvious that he is just swinging his arm back and forth, without connecting with anything. It looks as if he is dusting, not slaying someone. (01:23:50)
Revealing mistake: When the tanks are firing on the building near the end, some of the shots of shells hitting the building are reused. (01:35:00)
Revealing mistake: It is obvious that the actor, Ellar Coltrane, is watching and waiting for the cue for "Mason" to start drinking from his can of beer at the pool hall. (02:03:44)
Revealing mistake: Tanner Boatwright was used as a leg double for Augustus. In the part of the sex scene where they shoot from the feet up, you can see that the amputated thigh is thinner and has a slightly different colored tone of leg hair than Ansel's actual leg. (01:05:25)
Revealing mistake: Tommy picks up a chair and breaks it on a desk, but the chair breaks just before contact. (01:25:30)
Revealing mistake: During the plutonium heist, when the truck skids, tire marks from previous takes are visible on the pavement. (00:10:20)
Revealing mistake: Late on in the film; Arnie and the female officer kick in the door to one of his teams house. Unfortunately Arnie is in his 70s now and not as agile as he used to be, the door was open and simply pushed hard. Look at the door, it has no damage and neither does the frame. Also, the door barely opens past a hard push. As tactically trained operatives they would not have pushed the door if it was ajar either, they would have opened it slowly to avoid startling anyone inside and warning them.