Jason Brennen is startled awake from a sound sleep. A dark thought has entered his mind, leaving him perplexed and disturbed. Night after night the tormentor returns and he begins to despair of his sanity. Try as he might, Jason can't shake its shadowing pursuit. It lingers just beyond understanding on the fringes of his memory. Then the nightmares begin, depriving Jason of sleep; causing him to seek help. But, the thought continues invading his mind, trying to take control. It seems determined to push Jason to the brink of insanity. In desperation he gives in to its influence as the thought...