Revealing mistake: When the elderly inmate is pushed over by the other prisoners, a wooden train he made falls out of his clothing. It can be noticed that the man is just holding the train in his hand whilst falling and drops it when he lands on the ground to make it appear as if it fell out of his clothing. He was not meant to be holding the train as it was not shown being held in his hand at any previous point. (00:07:25)
Revealing mistake: When the Captain is tripped over by Ricky, his face lands on a plank of wood with nails sticking out of it. In the shot of his face getting impaled with the nails, we can see that the Captain has been replaced with a dummy. (00:08:50)
Revealing mistake: When the elderly inmate is telling the two prison guards he wants to go home to see his wife and kids, one of the guards kicks him, and he falls back, but the kick misses the inmate by a few inches. (00:11:50)
Revealing mistake: Uncle Ghost sets a headstone in front of Ricky and tells him to break it with his energy. He breaks a small corner on the headstone with his hand to demonstrate, however it can be noticed that there are visible cut marks on the corner that he breaks off before doing so, revealing that the corner had already been cut off and reapplied to make it easier for Uncle Ghost to chop it off. (00:20:55)
Revealing mistake: When the assistant warden stabs Ricky in the hand with his metal hook hand, in the close-up shots of Ricky's hand, it is apparent that Ricky's hand has been replaced with a fake dummy hand. (00:25:08)
Revealing mistake: When Hai jumps down from the cross, Kuang's body, that has been attached to the cross, is a dummy and not a human body. (00:34:37)
Revealing mistake: When Ricky hits the back of Hai's head, one of Hai's eyes blasts out of the eye socket. In the close-up shot of the eye falling out, Hai has been replaced with a dummy. (00:36:54)
Revealing mistake: In the close-up shot of Hai's stomach when he removes his intestines, it is apparent that the blood that was used is not real blood, but in fact red-coloured water. The blood shown here does not have the thickness that real blood has and drips way too much like water. (00:37:41)
Revealing mistake: Just as Ricky goes to lift up Hai, a wire can be seen attached to Hai to help lift him off the ground. (00:38:00)
Revealing mistake: When Ricky punches Hai after throwing him into the air, there is an X-ray image shown of Hai getting his skull pummelled in. In the shot after this, Hai can be seen swinging backwards unnaturally, revealing that he is being held up by a wire off-screen. (00:38:05)
Revealing mistake: When the inmates begin to confront the assistant warden after Kuang's death, head of the East Wing, Tarzan appears and smashes an inmate's head with his bare hands. The inmate's head has been replaced with a dummy prop head in the shot where his head gets smashed. (00:39:19)
Revealing mistake: When Sa shows Ricky that his tongue has been cut out, in the close-up shot of his mouth, it is apparent that his mouth has been replaced with a fake prop mouth. The skin, lips and teeth do not resemble how human skin, lips and teeth appear in any way. (00:42:02)
Revealing mistake: When the gang of Four show Sa the dead body of Hai lying on the bed, the body shown on the bed is a fake dummy body and not a real human body. (00:45:22)
Revealing mistake: When Wong Chun cuts the skin off Sa's lower face, in the close-up shot of his face getting skinned, it is apparent that Sa has been replaced with a dummy. (00:45:50)
Revealing mistake: When Wong Chun kicks Ricky across the courtyard after he sets the plants on fire, a wire can be seen attached to Ricky's trousers just as he begins to lift off the ground and get hoisted backwards. (00:49:03)
Revealing mistake: Whilst the cell is filling with cement, Ricky runs over to the steel door and bursts through it to escape. In the shot of him bursting through the door, we can see that the interior of the door is extremely thin and is barely a millimeter deep, revealing that it is a fake prop door and not steel. (00:53:45)
Revealing mistake: When Ricky punches Tarzan's jaw, in the shot where Ricky's fist goes through the bottom of Tarzan's jaw and up through his mouth, Tarzan has been replaced with a dummy. (01:02:20)
Revealing mistake: When Ricky's girlfriend commits suicide by jumping off the roof of a drug dealer's apartment building, the body that is shown falling to the ground is a dummy and not a human body. (01:11:28)
Revealing mistake: When a couple of the inmates are watching the assistant warden drag Fa out of his cell by sticking his hook hand into his mouth, it is apparent that the man being dragged by the hook hand is a fake motionless prop dummy and not an actual person. (01:18:36)
Revealing mistake: When the assistant warden and the bald inmate walk into Ricky's cell after not seeing him inside, Ricky reveals himself, grabs onto the bald inmate and punches part of his head off his body, killing him. In the shot where Ricky punches the inmate in the side of the head, we can see that the actor has been replaced with a dummy. (01:19:17)
