TedStixon

Revealing mistake: As Frank (in Larry's skin) pulls the knife out of Julia's stomach, we get a quick closeup of the wound. If you pay attention, some of the blood appears to be unnaturally thick and "goopy" and is "rolling off" of her shirt rather than sticking to it and staining it, revealing it's fake. A lot of fake blood recipes cause this issue... some will stick and stain the fabric, but a lot of it will kind of just roll off because it's sometimes thicker than actual blood.

TedStixon

Revealing mistake: When Julia first encounters the resurrected Frank, as Frank speaks, you can see where the makeup ends around his mouth, and see nice, normal flesh inside his cheeks a few times, even though he's meant to be a gross, rotting shell of a human.

TedStixon

Revealing mistake: When Frank's skin is skewered by the hooks in the beginning, it's pretty clear that the skin is just a thin sheet of flesh-colored latex with some fake blood and "meat" behind it. The skin is far too thin and "stretchy" and seems way too "detached" from the tissue behind it.

TedStixon

Revealing mistake: When the cenobites appear to Kirsty, you can unfortunately see where Pinhead's makeup abruptly ends around his mouth, just behind his lips, as he speaks.

TedStixon

Revealing mistake: When Frank skins the rat in front of Julia in a threatening manner, if you look close, you can see that the actor is simply running the knife through a pre-made cut in the dead-rat prop, and isn't actually skinning it. What really gives it away is that you can kind of see that the skin is already separated at the bottom and even briefly "bends" before the knife reaches it.

TedStixon

Revealing mistake: When Frank is solving the puzzle-box in the opening scene, you can pretty blatantly tell when they switch out the prop, because little lines, gaps and shadows appear on the box that weren't there before. (Since it wouldn't be possible for a single prop to do all the different "functions" of the mystical box.) It's most noticeable when the first moving part appears, and you can see several hard "lines" that weren't there in previous shots.

TedStixon