Revealing mistake: When Michael is unconscious in the freezer after the fight with Angel in the supermarket, there is a close-up of his face and you can see his real teeth behind the prosthetic ones.
Continuity mistake: When Angel, Danny and the Andies are running with the trolleys to the butchers in Somerfield, two others give cover fire and appear in the isle behind Angel and Danny. Camera cuts and they appear again.
Revealing mistake: The shot of Nicholas Angel jumping into the skip is a stuntman with a rather vividly dyed wig.
Audio problem: When SGT Angel is at the train station with his Japanese Piece Lily and is waiting on the bench, we see a British Rail Class 165 leaving, however the speed the train is going at is too slow for the matching traction sounds (the sound of the train going over gaps in the rails). Also the rear of the train does not match a Chiltern Railways 165, it looks as if it has been edited (although the number reads 165007). Later on, we see Angel almost dropping off to sleep and a fast train comes in and blows the horn, the horn sounded does not match the horn that would come from this type of train, it sounds more of what would come from an EMU version (possibly 365 or 465 Networker).
Continuity mistake: During the chase of the shoplifter, they pass by a group of youngsters graffitiing on a wall. Clearly visible is the graffiti the boys had just started spraying. However, after Sergeant Angel has apprehended the shoplifter, he brings him back to the end of the alleyway. Look up the alleyway and at the wall on the left (the one the youngsters were spraying on), you'll see it completely barren of any graffiti. Additionally, the number of boys that were there varies between 5 and 8 between shots. (00:30:43 - 00:31:58)
Other mistake: When Sgt. Angel meets Joyce Cooper at the hotel, she is making a crossword puzzle. She said "Fascist" and then read the definition, but that word is not 7 across as she says, but 14 down.
Continuity mistake: At the end, Angel's nose bleed changes instantly depending on the shot. (01:45:30)
Visible crew/equipment: When Angel is chasing the shoplifter, look in the car's bodywork and you can see the camera's reflection. (It's a black rectangle that moves along the cars body work). You have to look extremely carefully, and slow-mo may help but is NOT essential. (00:27:45)
Continuity mistake: In the pub scene where Angel asks Fisher if he has been stabbed before, Fisher's level of beer in his glass changes slightly depending on the camera angle. (00:19:45)
Visible crew/equipment: After Frank shoots the light thing on the ceiling and he gets away, just about when Nicholas says "He'll come round" and the camera is aiming down where Frank got away, look at the bottom half on the screen and you can see someone's/something's shadow moving.
Continuity mistake: When Angel pulls over the yellow car, there is already writing on his notepad. The notepad then is clear, and he starts writing in his notepad. (00:31:50)
Revealing mistake: When Angel and Danny are getting the pints at the pub, the same clip is used for the fresh pints being handed to Angel and Danny. (00:45:45)
Continuity mistake: When Angel is chasing the shoplifter down the lane, the lane changes in style instantly. From old style rock walls to garages and trees, instantly. (00:29:20)
Chosen answer: In the pub Danny demonstrates using a ketchup packet to simulate stabbing himself in the eye. Later in the film he returns Nicholas Angel's notebook, hiding a ketchup packet in it. He stabs the pocket with the notebook, causing the ketchup to leak and simulate blood.