The Call of Cthulhu

First published in 1928, "The Call of Cthulhu" is one of H. P. Lovecraft's best-known short stories. 

"The Call of Cthulhu" is the only story written by Lovecraft in which the extraterrestrial entity Cthulhu himself makes a major appearance.
It is written in a documentary style, with three independent narratives linked together by the device of a narrator discovering notes left by a deceased relative. 

In tales such as the iconic ‘The Call of Cthulhu’, Lovecraft reaches into the cosmos, bridging the divide between horror and science fiction. The extra-terrestrial ‘gods’ and cursed histories that would emerge from these stories now form the cornerstones of Lovecraft’s unique mythology: the Cthulhu Mythos. This fictional universe, built in large part by his friend and most ardent supporter August Derleth, has in the years since been reimagined in myriad forms, and continues to act as a haunted playground for countless illustrators, fans and authors.