Since many of Edgar Allan Poe's stories are of the gothic genre, horror is certainly an added ingredient to his tales. In "The Cask of Amontillado," for instance, the narrator is clearly not a reliably sane one. For, he declares in the exposition "the thousand injuries" that he has suffered and how he will be avenged on Fortunato. Since he has endured countless injuries, Montresor desires in his revenge to make his victim, Fortunato, suffer. Like a cat toying with a mouse, Montresor takes Fortunato into the catacombs and mimics the Masons to which Fortunato belongs, points to his coat of arms with its brutal message, tetters his victim to a wall, and then closes him in alive so that he will understand, finally, that Montresor is avenging himself. As the reader recalls, Montesor establishes the condition that a wrong
is equally unredressed when the avenger fails to make himself felt as such to him who has done the wrong.
All of these actions, juxtaposed with the uninterrupted calm and confidence of voice with which Montesor narrates, contribute to the horror of the torture of Fortunato, and to the macabre and haunting ending of the gothic tale.
Technically, Montressor did not actually bury Fortunato, though the location (in a catacombs) and the method (a four-sided wall) are closely related. Nor did Montressor actually kill Fortunato; he left his enemy to die of starvation (or possibly fright). The manner of the revenge allowed for the death of Fortunato without Montressor having to bloody his hands. Montressor's purpose was to exact a long and tortuous death upon Fortunato, but without the possibility of being found out. The mental torture inflicted upon Fortunato must have been enough to satisfy Montressor. For Poe, whose stories often included blood, gore and dismemberment, this was a different type of torture that still left a deep impact upon the reader.
The significance of Montressor's burying his victim alive may be interpreted on a more abstract level. The walls of the catacomb, which close in on Fortunato, may symbolize the emotional and psychological "walls" alcoholism seal around the suffer of this disease. Also, the parallelism may be drawn around the fact that death by alcoholism is often slow and lonely. Overall, the metaphor of the "walls" seem to be essential in this scenario.