I first read "The Cask of Amontillado" my sophomore year in high school. Though nothing supernatural happens in it, it has lived in my memory ever since as one of the most perfect horror stories I have read.
Edgar Allen Poe is of course one of the fundamental writers of horror and dark fiction. "The Cask of Amontillado" was first published in Godey's Lady's Book in November, 1846.
