Since the US bombing of Japan in World War II, the world entire has remained terrified of nuclear weapons. Even as scientists and scholars spent decades warning about the existential threat posed by technology that can literally end civilization, countries across the planet raced -- and race still -- to gain this capability for themselves. In tonight's episode, Ben and Matt ask: What actually happens in a large-scale nuclear war? (Spoiler, tune in for our upcoming episode: "What can I do to survive a nuclear war?"