"The Shambler from the Stars" is a horror short story by American writer Robert Bloch, first published in the September 1935 issue of Weird Tales. It was later included as part of his first published book, The Opener of the Way (1945), and his 1994 collection The Early Fears. As a Cthulhu Mythos tale it is notable for introducing the forbidden tome De Vermis Mysteriis (Mysteries of the Worm), and being a prequel to Lovecraft's own short story The Haunter of the Dark, which was dedicated to Bloch.
The story focuses on a nameless narrator who, in addition to being a college student, hopes to make a living as a pulp writer of weird fiction. Unfortunately, his earliest efforts at the craft are woefully inadequate and rejected by the magazine editors. As a result, he begins to yearn after the forbidden knowledge known only to those who are true practitioners of the occult, and begins sending letters of correspondence to various thinkers and dreamers from all over the country. One man in particular, a "mystic dreamer" from New England, tells him of the existence of certain nameless and forbidden tomes such as the Necronomicon and Book of Eibon. Soon afterwards, the narrator mails letters to various libraries, universities, and occult practitioners, hoping to secure the desired volumes. However, he is only met with both hostility and threats of violence. Undeterred, he then personally begins searching various bookstores around his hometown.
At first, he again meets with disappointment, but his perseverance eventually pays off and, in an old shop on South Dearborn Street, he succeeds in obtaining an occult volume known as De Vermis Mysteriis, which he knows was written by a reputed mage, alchemist, and necromancer from Brussels, Belgium named Ludvig Prinn, who was burned alive at the stake during the height of the witchcraft trials. Finding it to be written entirely in Latin, and not being able to speak the language, he once again contacts the New England mystic, who agrees to aid him in translation. The narrator then travels to his home in Providence, Rhode Island where at first he finds the mystic too hesitant to even open the volume, finding it reeking of evil and death, but eventually, upon the narrator's insistence, he opens it and is overcome by scholarly enthusiasm. While reading through, and occasionally translating, the book, he inadvertently stumbles across a spell or invocation on a chapter dealing with familiars which he believes to be a summoning towards one of the invisible "star-sent servants" spoken of in the frightful stories surrounding Ludvig Prinn.