Revealing mistake: In the scene with the press conference, as Chris is making her way to the front, journalists are holding cassette recorders out, as if seeking comment. The problem comes in that they are playing their recorders, but not recording, since the play buttons are pushed, but the red record buttons are not.
Revealing mistake: When Chris is asked to sign the calendar at the police station, Helen Mirren signs the calendar "Helen Mirren" instead of "Chris Harper."