"The Slithering Shadow" is one of the original short stories starring the fictional sword and sorcery hero Conan the Cimmerian, written by American author Robert E. Howard and first published in the September 1933 issue of Weird Tales magazine. "The Slithering Shadow" is the original title, but the story is also known as "Xuthal of the Dusk" in further publications. It is set in the pseudo-historical Hyborian Age and concerns Conan finding a lost city in a remote desert and encountering therein a Lovecraftian-esque demon known as Thog.
