In Arthur Conan Doyle’s work, it can sometimes be hard to tell where detective writing ends and where fantasy begins. The line between historical storytelling and, so to speak, “alternative history” is rather conditional. The author’s attention to each of the “lost worlds” is highly natural. A. Conan Doyle’s stories, devoted to the strange and incredible, seem to be created by a well-known hand of Doctor Watson who suddenly decides to describe not another adventure of the Great Detective, but a journey into a mysterious world.