1. He was tricked into the catacombs: Montresor, the narrator, lures Fortunato into the catacombs under the pretense of needing his expertise to identify a rare wine, Amontillado.
2. He chained Fortunato to the wall: After leading Fortunato deeper into the catacombs, Montresor chains him to the wall, intending to leave him to die.
3. He bricked Fortunato up alive: Montresor builds a wall of bricks, sealing Fortunato in the dark, cold depths of the catacombs, where he is left to die a slow and agonizing death.
It's important to note that Montresor's actions are driven by a desire for revenge against Fortunato for a perceived insult, highlighting the themes of revenge, betrayal, and the dark side of human nature in the story.