In "Beyond the Wall of Sleep", an intern in a mental hospital relates his experiences with Joe Slater, a backward Catskills mountain man and now inmate at a hospital for the criminally insane. The inmate was having very strange and vivid dreams which he described in a way seemingly impossible for a man of his limited intellect. The intern decides to use a device he built but never tested, a device that could be used for two-way telepathic communication to monitor the man's dreams. What he discovers is both astonishing and frightening.
