In the exposition we meet the two characters of the story, Montresor and Fortunato. The setting is the Carnival somewhere in Italy. Montressor tells Fortunado that he has what he believes to be a rare bottle of wine, called Amontialldo and he needs Fortunato to verify it as authentic.
We learn of the conflict between the two characters when Montresor tells the readers that Fortunato has insulted him and that he has been planning to get revenge on him.
The Rising Action takes place as Montresor leads Fortunato into his vaults to taste the Amontillado. Fortunato seems to be getting sicker and sicker, and drunker and drunker in the vaults but they press on.
Once the two men reach the end of the vault where this is a solid granite wall, Montresor pushes Fortunato against it and chains him to the wall in a niche.
After Fortunato is chained the wall, Montresor stops treating him kindly and begins to mentally torture him. He mocks his cries for help and begins to wall up the entrance to the niche.
Montresor finishes the wall and walks away with a sickness in his heart which he attributes to the mold on the walls. He tells the reader that no one has disturbed the bones for half a century.