Beyond the Wall of Sleep

In this eerie short story from horror master H.P. Lovecraft, a 40-year-old man from a backwoods community in the Catskills is confined to a mental hospital after committing a gruesome murder. The patient suffers a series of violent, trance-like episodes during which he recounts an epic battle against a mysterious, otherworldly entity. Are the fits merely the byproduct of a mental illness -- or is something much stranger going on?