Factual error: In the scene where Wolverine is shot in the head the bullet stays in place until it falls off. Wolverine's skull is indestructible Adamantium (that doesn't even bend slightly from the impact), and an object that applies a certain amount of energy towards another object has the same energy applied to it in return. Considering the bullet's high speed (which means high energy) and the fact that there is not enough material around Wolverine's skull to absorb the bullet's energy, the bullet should have bounced right out.
X-Men 2 (2003)
1 factual error - chronological order
Directed by: Bryan Singer
Starring: Hugh Jackman, Halle Berry, James Marsden, Ian McKellen, Patrick Stewart, Brian Cox, Famke Janssen, Anna Paquin, Bruce Davison, Alan Cumming, Rebecca Romijn, Kelly Hu
Continuity mistake: In the end, when the President is visited by the X-Men, he receives a blue binder, which is laid in front of him on the table. When they have left, you see a shot including the President's desk, and you can see that the only thing he has on the table are some sheets of paper, stapled in the upper left corner, opened up. Then the shot changes to a close-up of the President, and then back again, and you see the blue binder in front of him, closed, and the papers have disappeared. (02:01:40)
Pyro: You know all those dangerous mutants you hear about in the news? I'm the worst one.
More trivia for X-Men 2
Question: Why does Charles look out of the window in the end of the movie, when he's teaching a class?
Answer: Presumably he is sensing the presence of Jean/Phoenix.
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