The creation of suspense in 'The Tell-Tale Heart'

The narrator in the story is extremely hubristic, unreliable and unpredictable because he is delusional. Poe uses the hubristic and delusional narrator to create suspense. Poe uses irony to create suspense - the narrator insists that he is not ‘mad’ but his actions suggest otherwise. Poe shortens his sentences and uses more expressive punctuation to reflect the narrator’s escalating delusion. Poe uses sentence structure and punctuation to build tension in the lead up to the narrator's dramatic confession.