The article deals with the work of Algernon Blackwood, the British classic of horror and science fiction literature. His novels and stories’ central theme is manifestations of another world in everyday life. To analyze Blackwood’s worldview, the author uses the tools of the phenomenology of religion, in particular, Mircea Eliade’s ideas on the sacred and the profane dichotomy and the hierophany; Rudolf Otto’s theory of the numinous; and the phenomenological theories of W.B. Kristensen and G. van der Leeuw. The article analyzes how the theme of the sacred is revealed in Blackwood’s texts and with what means he creates the world of his religion. The article explores the concept of the “non-divine sacred” as applied to the work of Blackwood. In the concluding discussion, the fantastic world of Blackwood is compared with the world created by Howard Lovecraft.