Boston, 1926. Francis Thurston goes through documents left behind by his grandfather's brother, recently deceased under mysterious circumstances. He soon discovers the existence of a cult that worships ancient and unspeakable horrors. Mysterious murders, blood rituals in the depths of the Louisiana swamps, artists who descend into insanity after nightmarish visions, and a Cyclopean city that rises from the sea. Step by step, Thurston realizes that his relative's research got too close to the truth. In the