The 2003 short story collection, Shadows Over Baker Street, featuring eighteen stories by writers such as Neil Gaiman, Brian Stableford, and Barbara Hambly, is just one example of a postmillennial resurgence of Weird writing. This horror collection offers a selection of alternate Sherlock Holmes tales by contemporary writers, pitting the master of rational scientific enquiry against the terrifying monsters of H. P. Lovecraft’s mythos. In so doing, Shadows Over Baker Street makes a contribution to current debates about belief and knowledge, revising dominant ideas about the relationship between human perception and the material world. The stories put forward a double alternate, or ‘secret’, history. First, they partake of a tradition in Weird fiction of revising the history of human civilization to reveal aeons-old monsters from beyond the stars. Second, they rewrite the fictional history of Sherlock Holmes, inserting him into this Weird ontology. The collection thus draws on two modes of writing, detective fiction and Weird horror, and the contest between the two is unsettling. Typically, Sherlock Holmes stories shore up faith in modern systems of scientific and rational enquiry. In contrast, Weird horror disrupts Enlightenment and scientific narratives about knowledge in its suggestion that everything we know about the world is wrong. In a reversal of the usual Holmesian narrative, the stories in Shadows Over Baker Street encourage their readers not only to suspend their disbelief, but to surrender their faith in rational systems of thought. Holmes battles with phenomena he can never hope to understand, but in which belief is undeniable. In pitting rational disbelief against Weird speculation, the collection asks its readers to surrender to a Weird ontology. This ontology is resolutely material rather than supernatural, but it refuses to be quantified or represented by scientific modes of knowledge.

The Weird is a form of fantastic horror fiction that posits the existence of indescribable alien monsters and overturns traditional histories of human civilization. It aims to produce ontological and epistemological horror in its depiction of insignificant humanity within the cosmos. The narrator of H. P. Lovecraft's short story, ‘The Colour out of Space’ (1927) suggests this cosmicism as he ponders ‘unformed realms of infinity […] whose mere existence stuns the brain and numbs us with the black extra-cosmic gulf it throws open before our frenzied eyes’ (Lovecraft, ‘The Colour Out of Space’ 199).