Ph'nglui mglw'nafh Cthulhu R'lyeh wagh'nagl fhtagn

In his house at R'lyeh dead Cthulhu waits dreaming

The Call of Cthulhu is a short story by H.P. Lovecraft written in 1926. It was the first of his novels to introduce the race of beings known as the Great Old Ones, most notably Cthulhu, and the sunken city of R'lyeh. It is the definitive Cthulhu story for obvious reasons. It is also the name of a roleplaying game set in the world of Cthulhu, unusual because of its setting, and the fact that the characters are not superhuman (unlike in most RPGs), and as in most H.P. Lovecraft stories, slowly go insane as they learn the truth.

Summary

The main character in the story is a young man who discovers a series of notes left to him by his uncle, along with an "unnatural" sculpture. His investigation of these notes leads to the discovery of mysteriously similar cults that worship the same being as portrayed in the sculpture, who they call Cthulhu, said to be an ancient being from before the dawn of humanity that now sleeps in the sunken city of R'lyeh, waiting for the time to rise again, in both Alaska, and New Orleans. At the same time he discovered that artists all over the world, including the man who made this sculpture had been having dreams involving a "monstrous, cyclopean city" and the words Cthulhu and R'lyeh, which culminated on the night of the second of April. He later finds the diary of a sailor, the last survivor of the yacht Alert, which met and killed a ship of Cthulhu cultists in the middle of the ocean, before landing on a island that turned out to be the top of R'lyeh, and releasing Cthulhu, resulting in the death or insanity of the rest of the ship. The sailor escaped, and Cthulhu was trapped again as the city sank.