Factual error: The opening scene shows Donna graduating from New College in 1979. That is not possible, women were only first admitted in 1979.

Plot hole: If Bradley Cooper was able to "quintuple" his money every day in the market as he claims to have done, he would have been able to earn the $100k he borrowed from a loan shark within a few days, starting from $800. Alternatively, he is shown in one scene winning a pot in poker where he could presumably also make a large amount of "seed" money from gambling. There was no need to borrow such a small sum of money from a loan shark, making the entire sub-plot unnecessary.

Stan Podalak: Let me help! Let me help! I can help! I can help!
Michael Jordan: What can you do?
Stan Podalak: Well, I may not be very tall, but... I'm slow.
Sylvester: And large.
Daffy Duck: And a dork.

Trivia: There are several places where Edward Norton sees Brad Pitt for a split second before he actually meets him - beside the photocopy machine, talking to the doctor, at the testicular cancer group, when Marla is in the alley, and when watching TV when the waiters say "Welcome". Also Tyler is the one who steals the Camaro after Tyler and the narrator meet for the first time.

New this month Question: How did the military police chief know the parents were dead?

Continuity mistake: When the Dark Aster enters the atmosphere at the end of the film, its wings untwist as it descends, in most of the scenes afterwards and the hologram the ship's wings are still twisted, then later during the battle they untwist again.

Continuity mistake: Spot finds four other humanlike creatures and goes to them. Arlo is standing several feet in front of them. He begins to push some dirt by using his nose. A close-up then shows him using his nose to draw a circle around the five others but he is standing much too far away to be able to do this.

Continuity mistake: As Penny sneaks off, Brutus and Nero have collars on, with chains attached to the right side of their necks. In a reverse shot the chains are attached to the left side of their neck. (00:00:40)

Hamster

Other mistake: When the stormtroopers break into the control room, the stormtrooper on the right of the screen hits his head on the door frame. On the DVD release they've added a thump when he hits it. (01:18:55)