Welsh author Arthur Machen (1863–1947) wrote his most popular supernatural tales between 1890 and 1900, a period in which European culture felt itself to be on the decline and in which “decadent” art and literature rose up both as a reflection of and a contribution to this perceived cultural deterioration. While Machen's works have received little critical attention, a recent revival of interest in fin-de-siècle decadence has brought his supernatural tales into the literary limelight. Noteworthy examples of this interest include Julian North's treatment of The Great God Pan in Michael St. John's Romancing Decay: Ideas of Decadence in European Culture and Christine Ferguson's analysis of the same work in her PMLA article “Decadence as Scientific Fulfillment.” Indeed, Machen's supernatural tales could enhance and complicate any exposition of decadent literature and culture; they offer a unique vision of descent into the primordial that differs from the moral and psychological treatment of decadence in other popular works of the time, such as Wilde's The Picture of Dorian Gray and Stevenson's Strange Case of Dr. Jekyll and Mr. Hyde. Like Stevenson and Wilde, Machen employs themes of transgression and metamorphosis to illustrate his characters’ deviations from human nature. However, the forces at work in Machen's tales do not arise from the recesses of the human mind in its modern conception, nor do his protagonists sin primarily against society and the arbitrary nature of its morals and values. Instead, Machen locates mythic forces at work within his contemporary society to highlight a much older form of transgression and to challenge notions of degeneration that held currency at the end of the nineteenth century.