Revealing mistake: Gracie hugs the Russian waitress in order to have a better view of the disc hand-off appear on the monitor. As she raises her left hand that holds the book/camera lens, we see that the digital feed that appears on the monitor stays steady and level, even though she is raising the book/camera lens higher and closer to her face. Obviously the feed that we see on the monitor is not taken from the book/camera lens. (00:04:10)Super Grover
Plot hole: Peter goes into Carl's mind to save Catherine. When he's in there he sees the tank with the water nymph. On the tank are strange symbols which provide the FBI with the clue needed to find the latest victim. Makes sense so far. But, go back to the scene just after the FBI have captured the comatose killer and are looking in his basement. The FBI are looking at the contraption that the killer uses to suspend himself over the victim. On the contraption is the same symbol seen later on the water nymph's tank. Why didn't the FBI follow up the symbol then?
Continuity mistake: When Daniel is being chased by the Yakuzi in their black Mitsubishi Lancer Evo 6s, one of their Lancers crashes into the tanks. The car used for that crash is however a Lancer Evo 4, which is older than the Evo 6, and has a different front bumper, bonnet and rear spoiler. (01:17:25)
Continuity mistake: As Gal is in front of his pool, standing with his back to the rock face, an immense boulder is tumbling straight towards him. It comes down the mountain to his right. As it gets airborne it is still to his right. Camera cuts facing his right and it is shooting past his right side, still moving straight downward. All good. But as the camera cuts to the front of Gal, the boulder smashes into the pool a couple yards to the left side of Gal. (00:04:50)
Continuity mistake: In the scene in which Leonard writes on the back of his picture of Teddy, "He is the one. Kill him," we see a shot of Leonard placing the picture on top of his tan jacket on the bed as he goes to write on it. Then, it goes to a close-up of the picture in which the jacket has disappeared and the picture is lying directly on the blue bedspread. It actually happens twice within that same scene. (00:15:15)
Continuity mistake: When Mathew Perry goes to Chicago to meet with the head Boss, Bruce Willis' wife comes to talk with him at the hotel. In the scene where he is brushing his teeth he picks up the mouthwash bottle and swigs some, then sets the bottle down on the counter. The camera cuts back to her, then back to Matthew Perry, and the mouthwash is gone. (00:32:50)
Factual error: In the scene where the FBI agents have taken Giovanni Ribisi in for interrogation, one of the FBI agents says at one point "...and I want the whole C:/ Drive backed up on a floppy.", which is pretty hard to do, if not impossible, unless you've got about a 5Mb hard disk drive (depending on compression levels). But later on in the scene where Ribisi is actually doing it, he does it in about 10 seconds...with a 1.44MB floppy.
Continuity mistake: There are seven Wharvey Gals. Three on the stage singing, three with the wife, and one that she's holding. One of the girls even says that there are seven of them. Yet in the end, when Everett and his wife are walking down the street, there are only six. One that she is carrying, and five following.
Continuity mistake: Chris Rock and Morgan Freeman are outside of Rosa's apartment, looking in the trunk of Betty's car. The cut-out of Dr. David Ravell pops out. Chris Rock throws the cut-out on the ground and stomps on it. Chris Rock has on white tennis shoes. Later, when Chris and Morgan are inside Rosa's apartment, Chris Rock is wearing black tennis shoes when he is with the sheriff, taking his gun and handcuffs.