It's a deadly, yet beautiful, enemy: endless fields of poppies--the source of much of the world's heroin. In Narco-State - The Poppy Jihad, CNN goes to the front lines of the battle in Afghanistan—from the farmers and smugglers, to the authorities tracking them down. It's a fight the world cannot afford to lose.

Three million people reside in its shadow. But if it erupts - can they escape? This week, World's Untold Stories examines Italy's Mount Vesuvius, one of the world's most monitored volcanoes. At least one scientist believes it is not monitored enough.