The parallel is not obvious because no mirror is involved. It is the fact that camera is moving backwards in front of the actors who approach a closed door. The

The parallel is not obvious because no mirror is involved. It is the fact that camera is moving backwards in front of the actors who approach a closed door. Then Rod Taylor reaches for the handle and opens the door and the outside light shines in. How come the camera is not in the way at that point? Did it move backwards to the closed door? The answer is quite interesting. Let me know if you'd like me to spoiler it for you.