Poe was vexed by the old man's eye. It wasn't something he did but what he is. It was his eye. It was evil. It drove poe crazy. It was an eye of a vulture. After a while poe decides to take the life of the old man in order to feel better. This early on in the story builds thrill. "i have made up my mind to take the life of the old man , thus rid myself of the eye.''
poe would practice killing the old man until he did it on the seventh day. After killing the man he got rid of all the evidence. He carefully hid and cleaned everything until it was all out of sight. finally the eye would torture poe no more. "his eye would trouble me no more."
A neighbor heard the old man scream. So the police showed up. Poe acted normal. The police believed him. The he heard noises. The police seemed as if they heard nothing. Poe went crazy then snapped. He showed the police the evidence . "I admit to the deed"