This was a video that I received from one of my colleague. It's been spreading and sending around in the email and since I work in the security field and my company do help others to install the CCTV, I was rather impressed with the video.
However, I think that this video is a made up one as the video seems very fake, especially the ghostly effect. How will a ghost be so visible?
Anyway, focus on camera 4 itself.
(Those with weak heart or dislike scary thingy, think you have to think twice before viewing this video. But it isn't that scary to my opinion.)