The narrative of "The Cask of Amontillado" by Poe generates a mood of dreadful suspense that leads to horror.
In this disturbing story of deranged revenge and terror, the reader is in suspense from the beginning because of the ambiguities of the offense that Fortunato has purportedly committed against Montresor, and of the "redress" that Montresor has outlined. These ambiguities are created by the circuitous plan of Montresor that prolongs any definitive action as he seduces his victim with psychological tricks and provokes him with perverse puns.
The inebriated Fortunato is certainly no match for the devious Montresor. For, this man who prides himself as a connoisseur of wine is led deeper and deeper into the catacombs as he is deceived by Montresor who feigns concern that the niter is bad for Fortunato's cough. As they turn and twist through these chambers of the catacombs, the reader fears what will be the result of this subterranean venture. Furthermore, these winding movements of the men are often halted by Montresor's sinister puns such as the double meaning connected to the trowel and a mason as well as Montresor's agreeing with Fortunato that he will not die of a cough.
The dark and horrifying mood of Poe's psychologically disturbing story continues to the very end as Fortunato is walled in without the reader's ever having been informed of Fortunato's actual offense. Added to this, Fortunato foolishly laughs and incongruously urges Montresor, "Let us be gone," suggesting that Lady Fortunato and others are waiting for him. But, of course, Montresor has no intention of disassembling all the tiers of bricks that he has so carefully laid in what one critic calls "a profane rite." Perhaps, then, the real horror lies in what men themselves are capable of doing to others.