Continuity mistake: In the opening scene Chow Yun Fat shoots a man wearing a yellow jacket and green shirt - the shot goes through the lapel of the jacket and there is a splash of blood. A few frames later, as the man is falling out of shot, his jacket opens to reveal his shirt is unmarked. (00:02:20)
Continuity mistake: When John is with Meg, sorting out the details of his new passport, 2 goons come to get them. The movements of the goons in the regular shots doesn't match what John and Meg see on the closed circuit TV. The CCTV shows the man on the left getting ready to shoot the door, the next shot (non-CCTV) shows the man on the right shooting the door. (00:22:10)
Revealing mistake: After shooting in the door to Meg's office, the man in the darker jacket shoots the computer then steps into the room. John jumps him and grabs his gun (his shirt is unmarked in this shot). John then shoots him at point blank range. In the closeup of the shooting, the man's shirt is already torn - and the bloodpack/charge is visible through the hole - for a few frames before the gun is fired and the special effect goes off. (00:22:23)
Continuity mistake: The man in the darker jacket shoots the monitor of Meg's computer - the rear corner is destroyed. When John shoots the man in the light jacket the monitor is visible in the background and the far wall is visible through the hole showing that the monitor has been utterly destroyed. About 40 seconds later, the monitor is briefly shown undamaged. In subsequent shots the damage at the rear of the monitor is present but the screen is intact. (00:23:03)
Factual error: To provide cover, John turns on the carwash. However, it is unlike any carwash I have ever seen since it emits lots of foggy steam and no water. (00:38:00)
Continuity mistake: After being handcuffed and hit, Meg's lipstick is smeared across her face. When she is shown next, after the scene in the carwash, the smears are gone. (00:39:15)
Continuity mistake: When John and Meg are trying to escape the carwash in the car, in some shots the back window of the car is totally missing and in others there is a large section of shattered glass still there. (00:41:24)
Continuity mistake: When Meg is altering the passport, we get to see the photos taken in the photobooth in the arcade. The booth took 4 pictures of John in slightly different positions (e.g. in the 4th photo (not the last flash which signifies a flashback) his head is turned quite a way to the left); but the 4 photos are identical. Also John's hair in the photos is different than when he was in the arcade. (00:55:57)
Factual error: The sound effect used for Mr. Kogan's Desert Eagle for the shootout in the Chinatown kitchen is WAY too quiet. It almost sounds like a silenced pistol. Any gun buff knows how loud these hand cannons really are.
Factual error: In the arcade shootout, one of the replacement killers uses a Heckler & Koch MP5K hidden in a briefcase. However, he does not use the proper technique for this weapon. You should hold the case horizontally against your chest to be able to withstand the recoil. If you just walked & fired holding the briefcase at your side, you'd probably end up shooting into your own shin.
Factual error: During the scene when the main character is deciding not to snipe the cop in front of his children, the scope is on backward. The larger reticule is to the rear and the cap thumb release is to the front and on the wrong side. Not to mention that no self respecting sniper would chose a rifle with a CAR stock for a precision shooting. Not to mention a carry handle. Unstable long range system.