The story begins with the narrator admitting that he is a "very dreadfully nervous" type.
Ironically, the narrator offers as proof of his sanity the calmness with which he can narrate the story.
The story begins boldly and unexpectedly: "I loved the old man," the narrator says, adding, "He had never wronged me." Next, he reveals that he was obsessed with the old man's eye — "the eye of a vulture — a pale blue eye, with a film over it." Without any real motivation, then, other than his psychotic obsession, he decides to take the old man's life.
He can stand the horror no longer because he knows that "they were making a mockery of my horror . Clearly, the narrator, who has just finished the gruesome act of dismembering a corpse, cannot cope with the highly emotional challenge needed when the police are searching the house.
These two factors cause his heart rate to accelerate to the point that his heartbeat is pounding in his ears so loudly that he cannot stand the psychological pressure any longer. The narrator's "tell-tale" heart causes him to convict himself.
Consequently, from the psychological point of view, the narrator thinks that he is hearing his own increased heartbeat. louder [and] louder." The narrator was suddenly aware that the old man's heartbeat was so loud that the neighbors might hear it. He dragged the old man to the floor, pulled the mattress over him and slowly the muffled sound of the heart ceased to beat.
As he waits, the heartbeat which he heard excited him to uncontrollable terror, for the heart seemed to be "beating . The old man was dead — "his eye would trouble me no more." Again the narrator attempts to show us that because of the wise precautions he took, no one could consider him to be mad, that he is, in fact, not mad.
The question is, obviously, whose heart does he hear?
We all know that in moments of stress and fright our own heartbeat increases so rapidly that we feel every beat.
For seven nights, he opened the door ever so cautiously, then when he was just inside, he opened his lantern just enough so that one small ray of light would cast its tiny ray upon "the vulture eye." The following morning, he would go into the old man's chamber and speak to him with cordiality and friendship.
On the eighth night, he decided it was now the time to commit the deed.