Stories blending science fiction and horror, including a classic that predicted the terror of climate change. It starts with common mildew—mold appearing where it has never grown before. A strange kind of mold, it spreads across the entire globe in a matter of months. Although it’s harmless, it’s an indication of something much more terrifying. Without our noticing, the Earth’s climate has changed. But as the world’s greatest scientists rush to save the planet, they realize it may already be too late. The balance of nature has been disturbed, and mankind is about to become an endangered species. “The Great Fog” is a chilling piece of hard science fiction that predicted global climate change decades before it became a reality. Like the other stories in this volume—including “Eclipse,” “The Crayfish,” and other classics—it shows author H. F. Heard at his best. A spiritualist, scientist, and early advocate of environmentalism, Heard was one of the leading thinkers of his day. A colleague of Aldous Huxley, author of the legendary Brave New World, he used his unique background to redefine the budding field of science fiction, producing elegant, odd short fiction that still “makes the flesh creep [and] the conscience crawl” (Time).