A 45-mile wide caldera is brewing under one of the world's most famous national parks. What will happen when it finally erupts? Greg Breining explores the shocking answer to this question and others in this book, full of scientific facts but written for any reader. When this erupts, the world will be hit hard, with massive earth tremors as far as Tierra del Feugo and the Arctic ice-caps, tonnes of poison gases, enough ash thrown up to dramatically alter the weather patterns of the world and cause a nuclear winter. Previous volcanic eruptions have claimed a huge death toll - Krakato killed 36, 000; Icke in Iceland killed over 9, 300 people in less than an hour by releasing fluorine gases; Mt Uzen caused 14, 300 deaths in Japan in 1792, and Mt Tambora killed over 92, 000 people in 1812 - but this one has the potential to alter not only one continent but the entire world.