A morphine-addicted narrator recounts his harrowing escape from a German sea-raider and his drift onto a strange, upheaval-born landmass in the Pacific. There, amidst the stench of decaying mire, he witnesses a colossal monolith and a monstrous aquatic entity worshipping it. The story explores the fragility of the human mind when confronted with the vast, ancient powers lurking in the ocean's depths. It serves as a seminal introduction to a mythology where humanity is insignificant and the gods are monstrous.