Remember the bookcase-lined hallway with secret doors? Here is a video of the hidden doors in action. http://www.youtube.cohttp://www.youtube.com/watch?v=p2Z-8goyeOE&feature=youtu.bem/watch?v=p2Z-8goyeOE&feature=youtu.be It’s not just doors on hinges. Watch the action of the vertical trim piece in the middle, between the two sections.