Plot hole: Julia dies in the underwater escape trick tank because the axe couldn't get her out in time. However, if she was able to open the lid from inside the tank, get up, over, and down, then close the lid (all quickly, silently, and without assistance) when the trick goes properly, then there is no reason that the four men standing around could not have simply lifted the lid, either acting a key in the fake padlock to preserve the trick, or using a key if it's real. At this point she could have gotten her head above water and draped her hands over the side of the tank to stay up. That done, the crisis is over, and she must only wait to calm down enough to get herself down, or be assisted. Cutter built the tank, so he knew how strong the glass was. The only explanation for using the axe was to allow Julia's death, thus advancing the plot.
Trivia: During Borden's performance which ends with Angier shooting him, on at least two occasions the bill for the show can be seen off to one side. About halfway down is the name "Harry Dresden", the name of the wizard protagonist from the Dresden Files book series by Jim Butcher.
Trivia: The "Chinaman" in the movie was based on a real-life magician. He wasn't Asian at all, he just dressed and lived the part. The first English he ever spoke in his career were his last words. When a bullet catch went awry, he uttered the words, "My God, I've been shot" just before his death.
Alfred Borden: Everything's going to be all right, because I love you very much.
Sarah: Say it again.
Alfred Borden: I love you.
Sarah: Not today.
Alfred Borden: What do you mean?
Sarah: Well some days it's not true. Maybe today you're more in love with magic. I like being able to tell the difference, it makes the days it is true mean something.
Olivia Wenscombe: He wants me to come work for you and steal your secrets.
Alfred Borden: What does he need my secrets for? His trick is top-notch. He vanishes, and then he reappears instantly on the other side of the stage - mute, overweight, and unless I'm mistaken, very drunk. It's astonishing, how does he do it?
Question: In Angier's final preformance Borden watches Angier's duplicate drown in the tank. Does the other Angier still reapear for the audience, and take a bow? They never explain this in the film. If he does take the bow, Borden would never have been accused of murder. If he doesn't take the bow, how does the duplicate know not to do so? The duplicate would have no idea that Bordin was below stage.
Question: In the very last shot before the credits, the camera has pulled back to reveal a row of tanks containing dead Jackmans. Does this imply that not only did the Tesla machine replicate Angier, but also the tank? One assumes then that Angier has had the forethought to place a floor between where he materializes and the newly replicated tanks appear.