Continuity mistake: Sheila is clutching the phone to her chest with both hands, since Melinda is reaching for it to delete the butt-flexing video. The door chimes and the bearded man enters the store; in the foreground Sheila is in a different position with her arms crossed, and in a third one with her arms down at the next cut. And even more noticeable, a 4th different one as she walks away, holding the phone across the chest to the opposite side of her body all of a sudden. (00:07:50)
Continuity mistake: In the underground lab, Dr. Su offers to surgically remove the false memories he implanted in John's brain. He drills a half-inch hole in the right side of John's forehead, which leaves the right side of his face covered in flowing blood. John can't stand the pain, breaks free, and he goes on a rampage throughout the underground bunker, killing every UniSol in his path. As he fights his way through the bunker, the bleeding hole in John's head switches from the right side of his forehead to the left side, then back to the right side again. Also, in the last scene (an unspecified amount of time after the bunker brawl), John has no scar on his forehead at all.
Factual error: When the underground garage of the market is flooded, the car that Kyle and Heather are in does not flood. A car is not water tight like a submarine. Even though the water does not cover the top of the car, water would flood the entire car within minutes.
Continuity mistake: The position of Beth's truck facing her motel room (106 or 706?) changes during the time she is talking to Holly. Sometimes the truck is closer to the room next to hers (105 or 705) and to where Beth is standing. Also, the truck's front tires are different distances from the curb. (00:48:25)
Revealing mistake: Lazy prop department at work in the opening credits of this movie; look at the guest list. The second page and the first page are an exact copy and paste of the same names and addresses. (00:01:35)
Continuity mistake: In the car after Martin tells Hans about the throat slitting story, Billy and him get into an argument about the violence of the story. Billy says "It's going to be violent, it's about seven fucking psychopaths!" Martin then says "Hey!" But you can see in the back seat his mouth doesn't move for that. Then it cuts to a close up of Martin and his head is in a different position, facing Billy where he was looking out the window a moment before. (00:58:05)