The Masque of the Red Death
How we cite our quotes:
Then, summoning the wild courage of despair, a throng of the revellers at once threw themselves into the black apartment, and, seizing the mummer, whose tall figure stood erect and motionless within the shadow of the ebony clock, gasped in unutterable horror at finding the grave-cerements and corpse-like mask which they handled with so violent a rudeness, untenanted by any tangible form. (13)
When Prospero falls, at last a group of revelers overcome their fear and attack the guest who's killed their Prince. They discover, to their "unutterable horror," that the creature in the costume is the Red Death itself. The fear level has now reached its climax.