Witchcraft and paganism exert an insistent pressure from the margins of midcentury British detective fiction. This Element investigates the appearance of witchcraft and paganism in the novels of four of the most popular female detective authors of the era: Agatha Christie, Margery Allingham, Ngaio Marsh and Gladys Mitchell. The author approaches the theme of witchcraft and paganism not simply as a matter of content but as an influence which shapes the narrative and its possibilities. The ‘witchy’ detective novel, as the author calls it, brings together the conventions of Golden Age fiction with the images and enchantments of witchcraft and paganism to produce a hitherto unstudied mode of detective fiction in the midcentury.