There was a man who was nearly blind. He had never seen the face of his mother, his wife, or his child. He fumbled about when in his own bedroom.
One day, a scientist gave him a pair of experimental glasses and he was told that the more he used them, the better he could see but he must not wear them all the time, for they were powerful and their total effect on him was unknown. Some who had worn these glasses had eventually gone insane.
He began wearing these glasses and, in a few weeks, he could walk down city streets and recognize people at a distance. He wore the glasses all the time and he got to the point that he could see his loved ones faces for the first time in his life.
Then he noticed that he could see things that other people couldn't. It started small. He could see crumbs of food on a business man's suit and the footprints a person left in the grass.
Curious and maybe a bit proud of his new sight, he kept wearing the glasses to see what might happen next. Eventually, he could even see through walls.
then, he started seeing something new. There were things moving behind everything he saw. They were horrible things. Alien things. They were manipulating life as he knew it, making accidents and good luck happen to whatever end: he had no idea. Humans were playthings to these creatures.
He removed his glasses and threw them away. But, he could still see them.