The narrator is sentenced to death in court for committing heresy against the Catholic church during the Spanish Inquisition.
The narrator faints, and wakes up in what appears to be dungeon. He tries to measure the length of the dungeon, but he stumbles and passes out on the ground again.
He wakes up and finds bread and water next to him, which he eats and drinks. He continues to examine the dungeon, but trips over his robe and stumbles upon a very deep pit.
After drinking more water, he realizes it may have been drugged. He wakes up bound to a bed, and notices a blade attached to a pendulum swinging above his head.
As the pendulum descends upon him, he realizes that it is a blade. He then takes the steak he was given and places it on the strap to get the rats to chew through it and allow him to escape. But, as soon as he's free, the walls begin to cave in towards the pit.
Just as the narrator is about to fall into the pit, the French General Lasalle reaches out and saves him after they have conquered the Spanish Inquisition.