Graham Hancock: "There was a lost advanced civilization over 20,000 years ago that was nearly erased by a global cataclysm around 12,800 years ago." He describes how myths of a great flood and Atlantis-like stories worldwide point to the Younger Dryas event, a sudden comet impact or cosmic catastrophe that reset humanity, wiping out megafauna and advanced societies. What if everything we think we know about human history is wrong? He told Diary of a CEO how survivors may have passed down know...