Revealing mistake: The gang is starting to argue as they are running behind schedule. The big guy is holding Nicole Kidman at knife-point. The camera zooms in on her breathing heavily...so heavily that the 'metal' blade of the knife bends up and down. (00:29:00)
Revealing mistake: When Donovan witnesses a fatal traffic accident on a rainy night, he suffers a mild heart attack and collapses in the street. Although he's lying on his back, unprotected from the downpour, surrounded by rain striking the pavement in both foreground and background, closeups show that no rain strikes his face, his felt hat, or his clothing. (00:12:20 - 00:12:50)
Revealing mistake: Locked out of the house, Katie has to wander around naked. Or rather, in her skin-colored tight fitting underwear. (00:16:22)
Revealing mistake: In the scene of the 20th game (the following shot after Brad Pitt leaves the field) we see Jonah Hill looking at him. An extra to the left pulls out his smartphone (which in 2002 was years away from release) and proceeds to take a picture of Jonah Hill.
Revealing mistake: In the scene when they are travelling in the RV, the tea in the glass is perfectly still, even when the RV is obviously in motion. The tea should be jiggling in the glass.
Revealing mistake: When Anna's looking at her reflection in the mirror she starts rubbing her face vigorously. Look at her right cheek and you'll it's red before she rubs, result of multiple takes.
Revealing mistake: When Johnny English tackles the Queen at the end of the film, you can see knee pads worn by the stunt double under her tights.
Revealing mistake: When Umi is first descending the stairs in her house, her left hand clips through the left railing.
Revealing mistake: While Lynn is driving, the scenery outside the driver's side window goes white a few times and, other times, with intermittent specks of green tree leaves/shrubs. The white-outs are too low to be representing the sky. For a period of time, the lower third or so of her side window is a horizontal white bar. (00:02:20 - 00:03:38)