William Brown, a neurotic, self-absorbed musician determined to finish his prog-rock magnum opus, faces a creative roadblock in the form of a noisy and grotesque neighbor named Vlad. Finally working up the nerve to demand that Vlad keep it down, William inadvertently decapitates him. But, while attempting to cover up one murder, William's accidental reign of terror causes victims to pile up and become undead corpses who torment and create more bloody detours on his road to prog-rock Valhalla.