The narrorator telling us that he is not crazy and what he did was "ok". Quote: "I made up my mind to take the life of the old man."
The narrorator telling us about his plan to get the eye. Quote: "It is impossible to say how first the idea entered my brain." and " I made up my mind to take the life of the old man"
The narrorator suffocating the old man to death Quote: "I dreagged him to the floor and pulled the heavy bed over him"
The cops came to check on the house because someone heard a scream. quote: "A shriek had been heard by a neighbour, during the night; suspicion of foul play had been aroused"
The narorator confessed his crime. He confessed because he heard the dead heart still beating. Quote: "Dissemble no more! I admit the deed! --tear up the planks! here, here! --It is the beating of his hideous heart!"
I think the most suspencful element was, when he heard the heart beating. " It grew louder! louder! Louder!"