This still shocking movie made by Michael Powell in 1959 is not strictly speaking about hidden cameras, but it plays a key role in linking cameras and violence, and makes central what the critic Laura Mulvey has called "voyeuristic sadism". It is about a man who stalks and kills his subjects with a camera. In this opening pre-credit sequence, part of what is amazing is that we are placed in the position of the killer, that is, looking through the viewfinder of the lens. It is as if, course, nothing exists until it is photographed - the camera both the instigator and the record of that which occurs before it.