Supernatural Horror in Literature, H.P. Lovecrafts masters thesis, is a tour de force of literary analysis, tracing the origins of the horror genre back to its origins and beyond. In it, Lovecraft starts with humanitys earliest days and traces horror-lit through the centuries from Horace Walpole through Mary Wollstonecraft, to Algernon Blackwood and Arthur Machen, and on into the present day.