In the realm of sleep and dreams and internal forces, sometimes the most frightening disturbances can come from within us: visions that startle us awake, or experiences that are too disturbing to allow us a good night’s rest. We’re told that it’s all a figment of our imagination, and most of us have wrestled with a horrifying question once or twice before: what happens if our nightmares become reality?

In Episode 146 of the Lore podcast, host Aaron Mahnke is in top form as he delves below the surface of waking reality to focus on the phenomena of nightmares and sleep paralysis. Mahnke begins with a survey of the wildly off-the-mark explanations throughout history for the cause of nightmares. He also explains why we are prone to bad dreams at certain points of the night. Next he provides an overview of sleep paralysis–that sensation of a pressing, immobilizing weight upon the sleeper’s chest, accompanied by feelings of suffocation. As Mahnke demonstrates, such frightful experiences have been noted the world over long before the clinical term “sleep paralysis” came into use. Tracing the etymology of the word “nightmare” all the way to the start of the 14th Century, he elucidates the word’s roots in the idea of bedroom intrusion by a demonic force. Reaching the dark heart of the episode’s narrative, Mahnke shares a series of gripping stories involving seemingly otherworldly incitements of nightmares–by the likes of incubuses, witches, and ghosts.

I was very surprised that Mahnke never referenced the famous Fuseli painting, The Nightmare (pictured above), which is certainly relevant to the central discussion of “A Great Weight.” Also, I wish that Mahnke had delved a little further into the modern understanding of sleep paralysis, but these are mere quibbles. Appropriately stocked with chilling tales, this nightmarish episode is a dream come true for lovers of macabre lore (and Lore).