Revealing: After Dr. Lawrence cuts off his leg and is crawling towards the gun, if you look at his dismembered leg, you can make out the shape of his foot hidden beneath his ripped up slacks.

Revealing: When Adam is searching Zep for the key to the chain once he has found the tape recorder watch Zep's tummy - he's breathing.

Continuity: When Adam pounds on Zep with the toilet seat, he grabs his shoulder in pain. In the first shot of him holding his shoulder, his hand is soaked in blood. In the second shot, however, his hand is much cleaner. Submitted by MasterChief3624

Continuity: When Dr. Lawrence opened his envelope he got a key in it. When he tried it on the lock on his chain and it failed to open, Adam then asks to try it. Right when Adam asks for it, he puts his tape and envelope down separate, but when reaches for his tape again, it has ended up inside the envelope.

Continuity: When Larry is desperately trying to reach for the cell phone, he uses the box that it came in. When that doesn't work he throws it off to the side (his left) but when we see it again the box is back where it originally was (on his right).

Continuity: Adam's hacksaw blade snaps almost as soon as he gets it. However, later on (just after he gets electrocuted) we see it lying beside him with the blade in one piece. Submitted by Jon Sandys

Continuity: In the scene where. Lawrence and Adam find the 'X' on the wall, there is a continuity error. Right after they find the 'X', the lights are turned on and there is the shape of a square on the wall (the cavity where the box is hidden). Before they find the 'X' there is no box or any dirty lines where the cavity is.

Continuity: When Dr Gordon is going crazy, he throws the box to his right, but in the next shot it's on the left, then on the right again.

Continuity: When Alison gets the gun from Zep and aims it at him, the gun is in her left hand. In the next shot it's in her right hand, and then it moves back to her left hand again. This is not an artifact of changing camera angles, you can clearly see the different hands holding the gun. Submitted by Grigory the Wanderer

Revealing: In Adam's flat just as he starts beating Jigsaw's doll (Billy) up, you can see that he's not actually hitting the proper puppet, but a cheap replica. You can tell by the red lines on it's face, and there is no red marks where it's mouth is.

Continuity: When Larry takes the box out of the wall, it turns itself around from when he's holding it, to when it's on the floor (keep an eye on the box's padlock).

Continuity: When Larry looks at the picture with Zep at the window, from one angle the picture is all crumpled but in the first person view, it's smooth. This changes several times.

Continuity: When Dr. Gordon gets out of Tapp's car and is talking to him at the car window, the amount of shirt sleeve showing under his jacket changes between shots.

Visible crew/equipment: After the first call when Dr Gordon gets on the cell phone, a boom mike shadow is visible on the bathroom door.

Factual error: The Swedish subtitlers made Amanda's situation even more tragic, incorrectly translating her dead cellmate as her dead soulmate.

Continuity: When Dr Lawrance first notices the clock on the wall and tells Adam about it, the time on the clock is around 4 o'clock, but in a later scene after he is told he must "kill Adam by 6 o' clock," the time on the clock is much earlier, around 11-12 o'clock. That much time wouldn't have passed between seeing the clock and finding the tapes.

Revealing: When Larry notices the clock on the wall, he puts his hand on a pipe. Watch the pipe, it bends in and foams out when he takes his hand off it, revealing it to be made of foam.

Other: When Larry is taking the cigarettes out of the box, look at his hand. It has a white paint drop or white dust on it, but throughout the scene it disappears and reappears.

Continuity: Jigsaw's thumb moves between shots after Adam gets the mini cassette recorder out of his hands. You can see Jigsaw's thumb, in the closeup shot, slide down to a position where it's lying horizontal and flat on the floor as the mini cassette recorder is being slid out of his hand. In the next shot, an overhead, you can see that his thumb has moved and is now more curled and in a more vertical position to where just the tip is touching the floor. Jigsaw isn't dead, so he could have moved, but this shot is an *instant* cut, he had no time to move. Submitted by Nick Bylsma

Factual error: Dr. Gordon is seen in a close-up to be sawing through his leg, some inches above the ankle joint and the shackle around it. Considering the long bones of the leg (fibula and tibia) are very tough in a young man, it would take a long time to saw through by hand, during which Dr Gordon should have passed out from pain-induced hyperventilation then died from shock.