They

Continuity mistake: At the beginning of the film, the little boy has big brown eyes. 19 years later, when the boy is shown as an adult in the diner, he has big blue eyes.

Factual error: When Julia goes to see her childhood psychologist, there is a fish in a bowl sitting next to the window. This would kill a fish within a day or two because of the heat being magnified by the window.

Continuity mistake: In the scene towards the end of the movie when Julia is in the mental hospital, it shows her getting out of bed and trying the door, which is locked. The handle to the door is on the left side. But if you go back and watch the alternate ending and she goes to try the door, the handle is on the right side of the door.

More mistakes in They

Terry: What do you think went through Billy's mind when he did it?
Sam: The bullet.