Continuity: At the end of the film when Julia discovers the cans are all in order, she runs for the front door and see the stereo set up there. Then the husband comes from behind. In the following scenes where she goes to the door to talk to Ben, the stereo is gone.

Continuity: In the scene where Ben knocks on "Sarah's" back door with the apples, the sides of her hair are up and it is evident that there are no visible bruises on her face. However, the next evening at dinner, "Sarah" has her hair down and after moving her hair, a large, fresh bruise is observed by Ben. If this bruise was present, it would have been seen the night before when "Sarah's" hair was 1/2 up.

Continuity: When Laura Burney visits her mother at the nursing home, she arrives in a 1967 Mustang. However, when she departs the nursing home after her visit, her Mustang is now a 1966 model.

Factual error: In the dramatic final confrontation, the husband tries to shoot Julia, only to find that the gun is empty. The problem is that slides on automatic pistols like the one used in this scene lock open when the last round is fired. The slide on this gun is visibly closed, so it should still have a round in the chamber.

Continuity: When Sarah/Laura first sees Ben singing and watering the lawn, the view from the inside of her bedroom shows that the room/wall extends quite a ways to her right. But from Ben's viewpoint outside, Sarah/Laura appears in a corner window, with no possible extension of the room/wall to her right anymore.

Plot hole: Laura tells Ben that she moved to Iowa to be near her mother who's in a nursing home, but she hasn't seen her yet. Ben asks why, and she replies that she's not sure it's safe. Why would Laura say this when she's trying to keep her identity and situation a secret?