An unnamed prisoner condemned by the Spanish Inquisition. He possesses a highly sensitive imagination and frequently swoons. This tendency blurs the boundary between his conscious reality and subconscious dread. Stripped of his freedom and placed in complete darkness, he attempts to rationally calculate the dimensions of his cell while he fights off panic. His acute sensory awareness makes him particularly vulnerable to the psychological torture his captors design.

The unseen, collective religious authority figures who condemn the narrator to the subterranean dungeons. They specialize in psychological manipulation and prefer to inflict mental terror over immediate physical execution. They carefully monitor their prisoner from above and adjust the dungeon's mechanical traps to counter his survival tactics, ensuring his agony continues.

A large swarm of ravenous rodents that inhabit the subterranean prison. They emerge from the depths when they smell food. They serve as an additional source of horror and physical discomfort for the trapped man. Their overwhelming numbers and constant hunger alter the immediate physical reality of the dungeon.