Ghost Illusions in Clouds
The video pretends to show a "mysterious ghost", that can apparently be seen in a picture of the sky, purportedly captured by the uploader "and his friends while at home". The ghost is supposedly a black face in the clouds. It then shows a still picture of a cloud-filled sky. But at the end of the video, a negative image of Regan MacNeil pops up with the scream from What's Wrong?, extremely loud and repeated four times. After some seconds the text "You just got pranked by a screamer..." is displayed.
NOTE: The following video contains a screamer!