The Nightmare is a 1781 oil painting by the Swiss artist Henry Fuseli. It shows a woman with her arms thrown below her, in deep sleep as she undergoes a nightmare as an almost hidden horse looks on as a demonic and ape-like incubus crouches on her chest. Its erotic and haunting evocation of obsession became a breakthrough success for Fuseli. Critics were taken aback by its overt sexuality, since interpreted as anticipating Jungian ideas about the unconscious.