Continuity mistake: When the Prime Minister is preparing to make his golf swing, his shawl is alternately bunched up and then spread out smoothly.
Continuity mistake: In the second wedding scene the amounts of confetti everywhere, changes.
Plot hole: When Melvin receives the phone call from a lost Diana, he is staring at his goldfish, swimming peacefully in the bowl in his apartment. He unsuccessfully attempts to rescue Diana, then goes to the night club where he encounters an inebriated Ginger. He escorts her home, rebuffs her advances, and goes to his own apartment. The next morning, he goes to her job site, where, inexplicably, the goldfish has now taken up residence. Unless Ginger's flunky somehow broke into Mel's apartment and absconded with the fish, there is no way the fish could have gotten there on its own.
Factual error: When the Empress is dressing for the Chrysanthemum festival, bobby pins and hair pins are visible in her hair, not made available until the 20th century.
Continuity mistake: In the scene after the 'one year later' title, where Anderson wakes up on the couch, he is wearing red plaid boxers. The following shot shows him feeding the mouse, followed by a shot of Anderson again, but this time he is wearing grey underwear while he drinks pickle juice.
Continuity mistake: When Taj is proposing the challenge to Charlotte the close up shots of him show him facing straight on standing square, but the distance shots he is standing at about a 45 degree angle to her looking to the right to talk to her, not facing straight on to her. (00:35:20)
Continuity mistake: When young Kostya is standing on the table with the jump rope tied round his neck, its knot repeatedly changes position, from Kostya's front to his back.
Audio problem: [Blu-ray] When Mandy goes to wake up Red and Chloe, she says: "Hey! Hey, we need to get up, OK? Come on." The last two words were missed from the overdub, are not heard and are also missing from the subtitles. (01:08:15)
Continuity mistake: As Edward Norton rises and walks away, the child that is in Naomi Watts' arms is lying on his side. The angle then changes and instantly the child is lying face up. The moment is continuous as Norton is still there, moving away. (01:47:20)
Continuity mistake: In the first movie, the prince has a little sister. She's mysteriously missing from the second movie, as if she never existed in the first place. I know she wasn't important to the plot, but still.
Other mistake: After the piano is delivered to the Girl's house, we see her mom cooking. There's obviously nothing in the pan despite her vigorous stirring. (01:19:35)
Factual error: At one point, a screencast of a computer screen shows a video of Barry Brickman on the desktop environment of Windows XP (operating system, developed by Microsoft, released in 2001). However, the app that plays the video is QuickTime for Mac (which runs on Mac OS only), not QuickTime for Windows (which runs on Windows XP). These two versions of QuickTime are almost identical in every respect, except for their title bar (the narrow horizontal area above the video). (00:19:15)
Continuity mistake: Sylvia comes home after Pablo asked her to be his partner at the contest. She has her shawl covering her right shoulder in the first shot, bare shoulder in the next. (00:37:00)
Character mistake: Lucy says the source of the quote "To err is human" as Alexander Pope's "An Essay on Man." The quote actually originates from Pope's earlier work, "An Essay on Criticism."
Continuity mistake: When Marcus is being chastised for the clothing he is wearing in the dance room, you can see a reflected shot of him looking down toward his feet. In the next shot, he looks down again.