Continuity mistake: When the white car is stuck and the stones are flying, the window of a car behind the white car is smashed, however in the next shot, it's back to normal and is smashed again. (00:51:45)
Continuity mistake: At the end of the bridge scene, Jackie is talking to the CIA operative. She asks him if he has the disc. At this point his hair covers only part of his forehead. When he chucks the disc into the river, his hair fully covers his forehead. (01:40:05)
Continuity mistake: When they are driving away in the white car they go on their side and drive around and then get flipped back up and there is no damage to the car whatsoever.
Deliberate mistake: At the end of the movie when everyone is on the bridge, the one female cop roundhouses the bad guy, who is clearly a white male in his 50's, but his stunt double is an Asian man (with different colored hair). They use the same stunt man a few other times for people he doesn't even look like.
Factual error: The locations mentioned in the film are all over the world, including South Africa and Rotterdam. During the car chase through South Africa, it is very clear that all the locations in this car chase are in Rotterdam. For example, at one point the car drives down stairs through a shopping-mall, this is a well-known landmark in Rotterdam. As a matter of fact it is about 1 kilometer from the bridge used in the finale of the movie.
Continuity mistake: When the "smart" scientists are at the power plant one of them picks up a CB backwards and talks into it.
Continuity mistake: When the car is driven through the narrow alleyway, along the side of the car it is all dirty and scratched. But when they right themselves and drive off, there is no dirt or scratches.
Audio problem: Before Jackie puts on the Dutch shoes a woman with another pair of Dutch shoes is seen running away. A shot later she is seen walking away behind Jackie and you can't hear her shoes.
Revealing mistake: When Jackie falls from the helicopter, in the close-up of him falling towards the trees, you can see a wire coming from Jackie's' left; using slo-mo helps. (The use of slow motion is permitted if things such as crew or equipment are visible.)
Other mistake: When Jackie is falling through the trees at the beginning, you can easily tell he is on strings because he would hit the branches with a lot more force than he does, and also wobbles in certain ways which would be impossible to do in this situation.
Visible crew/equipment: When Jackie Chan is standing on top of the tower, and shouts "Who am I?", the camera starts to circle around him. When it does this, you can clearly see a guy in a white shirt standing underneath, and then hides away in the corner! It's really clear to see.
Visible crew/equipment: When the lab where the scientists are starts to blow up, if you watch closely on the table where the scientists are running from, you'll see a pipe which is blowing out sparks into the air to make it look like it is blowing up!
Revealing mistake: When it shows the bad guy at the shooting range, there is a guy in a red shirt doing target practice right at the beginning of the shot. He is fake.
Other mistake: During the final fight on the roof, it is possible to tell that one of the two bad guys is played by two different actors. The first time Jackie fights the one wearing the waistcoat, you can clearly see the actor's face. However, when the bad guy jumps over an air vent, doing a spinning kick, look at his face and you will see it is a different actor. In addition to this, it is possible to see that the second actor is shorter.
Continuity mistake: When Jackie and the reporter Christine are in the restaurant in Roterdam, he just found out that she tapped his phone call. She pulled her hair back to show him her earpiece - the next shot her hair is down. In the very next shot she's holding her hair back again.
Other mistake: When the helicopter crashed it was near a forest. When Jackie finds it later on it is in the middle of a desert.
Other mistake: When Jackie is running in the wooden shoes he sees a dog falling from a piano being raised in the air. In two of the four shots that the dog is seen falling, you can see that it is a doll.
Continuity mistake: In the scene where Chan is handcuffed and fighting he falls on his back and kicks a bad guy but his hands are free, then in the next shot the handcuffs are back on.
Audio problem: Jackie is holding on to the guy while hanging out of the helicopter when he asks him why he set them up. It is obviously not his voice.
Continuity mistake: During the fight on the roof at the end of the movie, at one point, Jackie is standing on the edge of the roof, and the camera is above him. There is a view of a car park at ground level, with cars in it. There is then a brief cut away, and, in the next shot, the car park is empty.
Answer: It's quite possible because most movies use dubbing (or "looping") as part of the post-production work to enhance the quality or fix minor sound problems. Sometimes a different actor's voice is dubbed over a minor on-screen character.
raywest