Factual error: A map in the office of Policeman Pierce Brosnan showing the "Hillside Lake" is Lake Constance (Bodensee) in the south of Germany. (01:11:00)
Factual error: At the point where Jared Leto is released from prison he is picked up in a 1960 Black Chrysler Imperial. As the camera rises it shows the date as 1954. The car is used a few more times in the movie.
Factual error: During the plane ride into France, the Paratroopers are holding/carrying their weapons by their sides. In reality, their weapons (M1 Garands, B.A.R.s, etc.) would be carried in special "bags" strapped to their parachute harness. This not only protected their weapons, but also secured them to their person.
Continuity mistake: When Sister Irene's habit is ripped at the back, you can see a bra strap on her left shoulder which disappears when she is seen at the front and when the camera is closer to her back (when she has the pentagram carved into her).
Audio problem: As Annie is trying to leave Joan's house and she starts to give Annie instructions on how to do the ritual, it's obvious the audio for Joan's lines was dubbed in in post as a lot of her speech doesn't quite match up with her lips. Especially when she's saying "Your whole family needs to be in the house". (01:08:00)
Factual error: The helicopter used during the exchange is a Mi2, which has not been in service with the Russians since the 1970s.
Continuity mistake: At the beginning of the movie, the teacher asks "Has Nicky's mom volunteered?" The guy answers "Emily?" with his arms down his hips, but he had his arms folded across the chest just in the previous shot. (00:03:50)
Other mistake: When the detective sends the traffic cam footage, a Gmail alert pops up. However, the dad is currently using Margot's computer, not his. He previously logged into Margot's gmail account on this computer so any alerts received would be Margot's mail, not his.
Continuity mistake: When Buster is shot, his hat with the hole in it disappears.
Continuity mistake: Spoiler alert: At the end of the movie "Rose" stabs "Miles." We see her pull out the knife and it looks like a Rambo-type hunting knife. After she stabs him, we see the knife covered in blood but it is a different type of knife. It looks more like a skinning knife or filet knife.
Continuity mistake: The clock time on the top right of the laptop screen near the start changes from Sun 17:59 to Sun 16:00. (00:08:39)
Audio problem: When Mrs. Hudson finds a package for Sherlock instructing him to open it before the trial, she says "I never even heard anyone knocking" whilst handing it to Watson, but the line appears to have been dubbed over as her lips don't match up with the dialogue.
Other mistake: At the end of the movie Lorraine has to remind Elise that she helped her once, implying they haven't seen, or spoken since. When Elise first meets Josh in the 1st insidious she tells Josh that her and Lorraine have been friends for a long time, implying they talk or see each other regularly.
Suggested correction: That's debatable as the word "friend" does have to do with semantics. I have friends I have not spoken to in a long time, or speak with rarely, but still consider them friends due to our history. Others would say that's not a friend as that's not what they think of when they hear the word "friend." So it does depend on the individual person. It's also quite possible this is what they told Josh as the cover story for why she was contacted since they initially didn't want him to remember his past.
Other mistake: Daphne's dad drops the Legitimate Tulip badge in front of her so she'll avoid getting hurt, but when we see him do that, he does it before the warning for the ball is heard and seemingly not looking at the danger (especially in the second shot, when he is peeking from the corner). So his action makes no sense. (00:16:55)
Deliberate mistake: The movie is set in "Harburg County", Pennsylvania, but there is no county in Pennsylvania called "Harburg." (00:13:38)
Continuity mistake: Jeffrey downs all his whiskey, but in the following shot his glass is still half empty. (01:35:50)
Revealing mistake: Davey at the beginning of the movie is looking at the newspaper he's delivering to Mr. Wayne Mackey. Just from a glance at the page you can tell that something is off, since the article supposedly about a missing boy appears to be written entirely in first person. Upon closer inspection, turns out that it's filler text from chapter IV of Robert Louis Stevenson' s "Treasure Island". (00:01:30)
Continuity mistake: When Vera and David find the old camera and video tapes, David picks up the camera briefly before putting it back down. When he puts it back down, he places his thumb on top of it. In the next shot, his thumb is away from the top and along the side. (00:16:56)
Continuity mistake: When Jason lunges at Batman with his knife, there is a pile of garbage by the wall where he lands. In the first shot the barrel by the garbage is wooden. But in the next shot it's suddenly a metal barrel/drum. It then changes back to a wooden barrel again. (00:04:20)
Continuity mistake: The clothes Tyler and Kassi were wearing at Kassi's house were not the same when Kassi came to dinner that day at the Burnside's house. It seems unlikely that BOTH would change clothes before dinner. (00:31:49 - 00:32:40)
Suggested correction: Apparently they did. It was probably Tyler's idea, presenting Kassi in the best possible light to assuage suspicion and maintain his image as a good Christian Boy Scout.