Continuity: In the very beginning of Saw 2 when the informant awakes and realizes where he is and suddenly gets up from the chair there is a brief shot of him from the rear. If you look closely the leather waistband for the trap is completely loose, but when the camera quickly switches to his front, it shows the leather waist band tight around his waist.

Continuity: When Matthews' friend is watching the puppet on TV at the beginning of the movie, the channel indicator on the television keeps changing from displaying channel 3 in one shot to being covered up with duct tape in the next.

Continuity: In the opening scene when the informant is about to cut into his eye they show a close up of the knife just centimeters away from his eye ball. There is minimal blood only in his eye but nowhere else, where in the cut before it the whole area around the eye is covered in blood.

Deliberate "mistake": In the opening scene, the helmet closes on the guy's head. Inside there are spikes on all sides, but when his head falls to the ground the blood only comes out the bottom. The spikes should have also gone into the other side of his head and blood should have run down his face to the floor.

Continuity: When Mathews and the female agent are talking about the first victim, Mathew's head changes position slightly as the camera cuts back and forth. It is leaning to the right in one shot, then to the left in the next, etc. Very subtle, but it's there.

Visible crew/equipment: Crew is reflected in one of the large white SWAT vans which pulls up outside Wilson Steel factory.

Continuity: After Amanda falls into the pit of syringes and is dragged out by Eric's son, she is covered in blood from being stabbed with many syringes, but in every scene after that she has no blood stains on her skin or clothes.

Trivia: In the room with the razor blade box, if you look at the top of the frame, you can see a lock with a key in it. If the actress walked a few feet further, she could've unlocked the box and gotten the syringe. Obviously this would've defeated the purpose of her dying, but interesting to point out. Confirmed in DVD special features.

Continuity: In the scene where Emmanuelle Vaugier walks into the room with the clear box trap hanging from the ceiling, in the middle of the two hand openings is a syringe with the antidote. It is filled with significantly more in the close up shots, than there is in the full shots which show a lot less in the syringe.