Other mistake: *Spoiler Alert* The strength of the underwater suits is wildly inconsistent. Rodrigo's suit almost immediately cracks and implodes, killing him. Paul's suit is easily ripped open by the creatures, also killing him, but Norah is repeatedly slammed into the sea floor by one of the creatures and her suit remains remarkably intact.
Suggested correction: It is stated by one of the survivors that one of the helmets was damaged. Rodrigo had the damaged one.
Actually, that's not completely accurate. She says something like "Faulty, I knew they were faulty." That also doesn't account for the fact that the creatures tore Paul right out of his suit, but couldn't seem to do the same with Norah.
His suit was faulty. He noticed a crack when he first picked it to put it on.
Other mistake: The Volvo the woman is driving has a front Oregon license plate numbered 643 ODS, but her rear license plate is 902 CSM. (00:02:55 - 00:03:45)
Other mistake: An aerial shot of the woods is green instead of showing Fall foliage. When they are leaving, there's just as much - if not more - green leaves on trees than when they got there and it is after Thanksgiving (late November when there should be Autumn foliage, if any, on the trees). (00:18:29 - 01:24:13)
Other mistake: The woman who checked into the Mercer hotel said she thought the reservation was under "Perratti." Bart initially gave her Room 109, but switched to Room 124 - where he had hidden cameras - saying the room was nicer and had French doors that gave access to the pool area. The woman's husband, expecting to meet his mistress, went to the French doors and knocked to get inside. He should have gone to the room that was initially assigned because he could not have known Bart switched to Room 124. (00:08:52 - 00:10:05)
Other mistake: When the white mouse runs to save the brown mouse, he runs at normal speed, but the witches move in slo-mo for reasons unknown. (00:47:23)
Other mistake: Jude would not be able to write that neatly - especially that fast - while holding a floppy notebook in the air. The right half of the notebook was sagging while he wrote three perfectly lined rows ("I told you not to make him mad."). (00:46:03)
Other mistake: A crow crashed into a bedroom window, causing a small hole in it with radiating cracks. There was blood splattered around the hole as well as two long downward/ vertical lines of blood. Although it is possible for a bird to crack a window, it is much more likely that a bird breaks its neck without causing damage to the window. In the event that this crow did put a small hole in the glass, at least some fragments of feathers should have been stuck around the hole, but there were not any. (00:06:55)