Revealing mistake: When the man shoots a target next to Jack's second cousin's head you can see a shot of him pointing his gun. It is clear there is a pole supporting the gun. (00:20:35)
Revealing mistake: There is an obvious shot splice of the elevator reaching the floor with Jack on it and one without him. The position of the elevator changes ever so slightly and you can tell the difference in the light coming from the elevator. (01:12:30)
Revealing mistake: When the chopper is about to shoot out the elevator, on the right is a pair of guns and on the left a gatling gun. At the end of the scene the guns have switched places, with the pair being on the left and the gatling gun on the right. Flipped shot. (01:16:10)
Revealing mistake: When Arnie flips his car sideways to avoid the Texaco truck, the stunt driver is very obviously not Arnie.
Revealing mistake: When Slater jumps down to the next house to chase Benedict, you can see the face of the stuntman.
Revealing mistake: When Jack Slater is about to play chicken with the guys in the pickup truck, it's a stunt driver. (00:30:55)
Revealing mistake: When Arnie is talking to himself as actor Jack Slater, right when he says "You're the best look-alike I've seen" his eyes are looking slightly sideways, away from Jack, and not where they should. Obviously Arnie was talking to an empty place but missed.
Revealing mistake: After Slater jumps out of the house and it explodes, when the cop car flips over, the air ram used to flip it over is visible.
