When they get there, there is no Amontillado, but there is a hole in the wall, and Montresor begins to lock up Fortunato.
As the last few bricks are laid, Fortunato yells for Montresor to stop, but it is too late. The revenge had already been done, and he couldn't back out.
Before he finished laying the bricks, he threw the remains of the flambeaux in the tomb, and heard the jingle of his bells. Montresor claims that it's been 50 years since this happened and no one knows except for him.