Revealing mistake: Any time when the two girls are in hell's corridors and running around, you see these corridors as stone walls, yet whenever they back up against one of these walls, you can clearly see they are merely rubber sheeting overlayed on a framework as the rubber sheeting bends and contracts very clearly.
Continuity mistake: In the scene where Channard kills the original Cenobites, the collar of Pinhead's outfit undergoes visible changes. First it leaves his throat exposed but covers the rest of his neck. After Channard turns him back into a human, the collar then covers his entire neck. Finally, the collar completely disappears a second before Channard slashes Pinhead's throat.
Revealing mistake: When we see Julia in Channard's house, she is dripping blood, as she is skinless. From where she is standing, she would have had to walk across the room, dripping blood, but the carpet is very clean, excluding the area where she is standing. (00:34:35)
Continuity mistake: At the beginning of the movie, policemen are inspecting the deceased Rory's house to retrieve the bloody mattress for Dr. Channard yet at the end of the first Hellraiser, the house completely collapsed.
Plot hole: When the policeman asks Kirsty at the beginning who came when she solved the box she says the Cenobites; she had no way of knowing what they were called. Frank only told Julia; Kirsty didn't hear it anywhere and the Cenobites themselves didn't tell her either.
Continuity mistake: After Julia punches her arm into Franks' body and grabs his heart out from his skinless body, in the wideshot after she has grabbed his heart out her face is clean, but in the next closeup there is suddenly lots of blood on her chin.
Continuity mistake: When Browning is cutting himself on the mattress, in one shot his right shoulder is covered in blood, but then in the next close up of him, the blood has gone. (00:29:35)
Revealing mistake: When the Cenobites appear in Dr. Channard's office, the curtains are ripped away from the window. You can see the string that rips them away. (00:52:00)
Continuity mistake: After Tiffany solves the box and it closes itself, all the doors to Hell should have closed up again too as the closing of the box means the closing of the doorways; it happened in the first Hellraiser when Frank died the first time and Pinhead closed the box so they could return to Hell.
Revealing mistake: Several of the bodies hanging from the rafters in Channard's house that Julia had killed were obviously mannequins. Real dead bodies would hang heavily and slack from their bonds but at least two that I could make out weren't weighing on their ropes at all; they were posed, standing dummies. (00:45:05)
Revealing mistake: When Pinhead becomes human again and gets his throat slashed, you can see the black net-material behind the fake skin that provided the blood.
Continuity mistake: When Frank came back in the first film, he was little more than goo on bones but when Julia comes back she is much more whole. True, she had a lot more blood to use than Frank to begin with, but it still took Frank three bodies' worth of blood to look the way she does when she comes back.
Plot hole: The mover shouldn't have been pulled into the mattress because he didn't bleed onto it, which is what was required before, for Julia to come back.
Revealing mistake: When Frank grabs Kirsty when she finds him in the hell room, he grabs her and throws her into the stone wall. As she is thrown into the wall it bends like rubber and buckles under the impact.
Revealing mistake: When Kyle goes into the dead-body room, there is a shadow of a hanging dead person on the wall next to him. The shadow of the open door on the wall on the other side of him shows that the shadow of the body shouldn't have been there as the light would have to have been coming from the very far wall. When Kyle is looking around you can see that the only light source is the high windows on the left side of the room.
Revealing mistake: When Kirsty is confronted by the Cenobite doctor, Dr. Channard, there is a huge gust blowing towards her. If you look behind her, there is a suppossed stone wall, which appears to be flapping in the wind, revealing it is merely a fake set wall.
Continuity mistake: When Julia shuts Kyle into the room full of hanging bodies, she begins to kiss Kyle, then starts to suck out his blood. After she sucks all his blood out, between shots the amount and position of blood over her lips and chin, changes. (00:46:55)
Continuity mistake: When Julia emerges from the mattress and kills Browning, the mattress becomes completely saturated with blood. Then when the mover comes to take it away at the very end, there are patches where the mattress is clean. Then again, when he is pulled into it and his friend comes into the room, it is saturated again.
Revealing mistake: In the scene where Kirstie is in Hell searching for her father, she is running up and down Hell's corridor's, becomes winded and stops. As she does so, she slaps herself against a concrete corridor wall; when she does this, you can see that the "concrete" wall looks more like a rubber covering, as it moves with her. (01:01:50)