Continuity mistake: In the car at the start, when Hamilton says it's like the fourth blackout today, Michael corrects her and says it's the fifth. When he says this, he is leaning forwards some as he looks up out the windshield with his mouth partly open. It cuts to a different angle and suddenly he's leaned back in his seat fully and his mouth closed. (00:01:30)
Continuity mistake: In the first WW2 flashback the protagonist is handing the various items to the Nazi doorman. When he puts down the pen, he is doing it with a left hand in the table close-up, but he picked it with his right, as the left arm is busy holding the coat. (00:02:05)
Continuity mistake: When Stallone kills the bad guys with skull masks in the corridor of the bar, his motions pointing the pistol don't match the positions of the lemming-like goons he hits. For instance he has the gun all the way to his right for the first one he kills, but the guy is shown with a hole opening in his forehead while he's in the middle of the corridor. (00:29:00)
Continuity mistake: The mayor suffers a bleeding head wound while evacuating City Hall. Several scenes later he is shown with no wound at all. Not even his hair is mussed. (00:40:30 - 00:46:30)
Continuity mistake: When Will comes out of the garage to get Teresa, he has an alien's tentacle attached to him. When he and Teresa go in to the garage, he no longer has the tentacle attached. (00:34:25)
Continuity mistake: At the beginning of the movie Nya checks out of the leaking sink. The rag changes place after it cuts to her looking at the pipe, but she never moved it. (00:04:10)