«The Statement of Randolph Carter» by Howard Lovecraft

"The Statement of Randolph Carter" is a short story by American writer H. P. Lovecraft. Written in December 1919, it was first published in The Vagrant, May 1920. It tells of a traumatic event in the life of Randolph Carter, a student of the occult loosely representing Lovecraft himself. It is the first story in which Carter appears. Its adaptations include the film The Unnamable II: The Statement of Randolph Carter.
"The Statement of Randolph Carter" is the first person testimony of the titular character, who has been found wandering through swampland in an amnesiac shock. In his statement, Carter attempts to explain the disappearance of his companion, the occultist Harley Warren.
Warren has come into the possession of a book, written in an unknown language, that he forbids Carter from seeing. Carter mentions that Warren has other "strange, rare books on forbidden subjects", several of which are in Arabic.
From his mysterious book, Warren apparently deduces that doors or stairways exist between the surface world, and the underworld, through which demons may travel. He encourages Carter to travel with him to the location of one such portal, an ancient graveyard near Big Cypress Swamp…
Famous works of the author Howard Phillips Lovecraft: At the Mountains of Madness, The Dreams in the Witch House, The Horror at Red Hook, The Shadow Out of Time, The Shadows over Innsmouth, The Alchemist, Reanimator, Ex Oblivione, Azathoth, The Call of Cthulhu, The Cats of Ulthar, The Dunwich Horror, The Doom that Came to Sarnath, The Festival, The Silver Key, The Other Gods, The Outsider, The Temple, The Picture in the House, The Shunned House, The Terrible Old Man, The Tomb, Dagon, From Beyond, What the Moon Brings.