Revealing mistake: When Linderman dashes at Jason and impales him with an American flag, Will is dragging Lori (who is supposed to be unconscious). He's dragging Lori by her arms... but when he suddenly reaches behind his back with his right arm, her right arm stays up in the air. (01:13:50)
Deliberate mistake: When Jason throws Freddy to the wall in the burning house, you can see a window on the wall. Now, the distance between the window and the corner of the wall is about five feet. This gives Freddy space enough to hit the wall and not hit the window. However when Jason picks Freddy up you can see the distance has increased to about one feet. It's like they've put in an extra window where there should be a wall instead. (01:14:30)
Visible crew/equipment: When Freddy is brought into the real world and is fighting Jason in the cabin, look carefully as Jason picks up Freddy and pushes him out the window, you can see a cable attached to Freddy's chest in a close up. (01:14:35)
Revealing mistake: In the final fight scene where Freddy and Jason are outdoors, Freddy gets his leg caught in a rope and is hung upside down. This causes his pant leg to rise revealing an unburned limb, which obviously was not covered with make up. (01:19:25)
Continuity mistake: When Freddy and Jason get hit by the cart at the construction site, they land next to each other on the dock. But in the next shot, we see Jason getting up quite a distance away from Freddy. (01:20:10)
Continuity mistake: After Freddy and Jason lands on the pier you see Freddy crawling facing forward. When it cuts Freddy is suddenly looking backwards at Jason. (01:20:15)
Revealing mistake: In the fight scene nearing the end, Freddy cuts off Jason's fingers and slashing sound is heard. However you can tell that he completely misses Jason's hand, and in addition you can see the pre-made cuts that indicate where the fingers will fall off. (01:20:35)
Revealing mistake: When Freddy and Jason are fighting towards the end of the movie, Freddy cuts Jason's fingers off so he drops his machete. But when Freddy catches it you can easily see that it isn't a real one (it's made of rubber, or something like that). (01:20:40)
Continuity mistake: In the end of the movie when Jason comes through the water stabbing Freddy with his own glove, you can see the spikes only coming out of Freddy's chest. When it cuts to Freddy falling to his knees, the whole fist and parts of his armwrist suddenly has gone through his chest. (01:24:00)
Revealing mistake: When Lori decapitates Freddy at the end, it's obvious Freddy is a dummy (slow motion can help but isn't essential). (01:24:35)
Revealing mistake: In the fight scene at the pier, after Freddy and Jason get thrown into the air by the carriage that smacks into them, they land on the pier in sort of slow motion. Watch Jason's left knee as he lands, you can see a kneepad.
Plot hole: There's no way Jason could decapitate Blake's father the way he did without also decapitating Blake, who was sitting next to him sleeping.
Suggested correction: Maybe he set him up that way? His father did leave before this happened after all.
Revealing mistake: When Jason is slicing kids at the party, you can see the padding under their shirts.
Plot hole: In the institute, Will's friend gets out of his room to get the guard's keys. He couldn't have gotten out of his room because there isn't a handle or door lock inside the room.
Visible crew/equipment: In the scene where Lori wakes up in the police station and follows the dropping blood, she turns a corner because she hears a little crying. Right after she turns the corner, the cameras show office windows. You can see someone sitting down and a cameraman on his knees.
Visible crew/equipment: In the dream fight between Freddy and Jason, you can see the wire that holds the machete up when Freddy catches it after Jason swings it.
Plot hole: The sheriff orders a 24 hour roadblock on the town, yet the van has no trouble driving to Crystal Lake.
Continuity mistake: When the girls are at Lori's, just after Kia asks them if they think she needs a nose job, the lights flicker. When they flicker Kia is holding a compact in her left hand and she begins to close it. Both hands are up by her face but then the angle changes to a wider shot and her left hand is empty and on her lap and the compact is in her right hand as she places it on the sofa.
Plot hole: Linderman didn't know who Jason was after the rave massacre, calling him a "psycho in the hockey-mask", but later in the film when Stubb's is telling them (Will, Lori, linderman, Freeburg and Kia) about thinking Jason is a copycat, Linderman suddenly acts like he knows who they're dealing with when he didn't before. "I've seen what he can do, he's the real Jason."
Continuity mistake: In the fight scene on the pier, just after Freddy has sliced off Jason's fingers, Jason blocks the machete, Freddy slashes him with the glove and then cuts Jason's chest with the machete and raises the machete for a downward blow. They are now standing face to face. However, when Freddy makes this cut, Jason's back is all of a sudden turned, enabling Freddy to cut his leg from behind. There was no time for him to turn around between cuts.
