Days after he murders his wife with an ax and then hides her body in the cellar walls, several policemen visit the narrator. They come into the house to observe the premises. Not wanting to arouse suspicion, the narrator plays along. He accompanies the police as they go through his house and boasts to the reader that he was calm the entire time, his heart beating as steadily "as that of one who slumbers in innocence." After what they presume to be a thorough search, the police make ready to vacate the house. Then, the narrator makes his fatal blunder.
The narrator is as arrogant as he is remorseless. He tells the police that the walls of the house are incredibly secure and then taps the wall with his cane for good measure—at the exact location wherein his wife's corpse has been hidden. A great cry emits from behind the surface, arousing the terrified attention of the policemen. They break down the wall, revealing the black cat sitting atop the wife's rotting body. Whether the cat somehow got into the wall without the narrator knowing or has appeared there supernaturally, the narrator's arrogance becomes his undoing, and this leads to his apprehension by the police.