The Most Dangerous Place in the World – Rafael Grossi is the Director General of the International Atomic Energy Agency (IAEA). Grossi's most urgent mission: trying to reach an agreement between the Russians and the Ukrainians to protect Europe's biggest nuclear power plant in Russian-controlled Ukraine. A meltdown could lead to a nuclear catastrophe bigger than Chernobyl. Lesley Stahl reports. The Panini Sticker Phenomenon – The World Cup begins Sunday in Qatar. Still, for millions of soccer fans, the excitement started weeks ago when the Panini stickers featuring their favorite players shot onto the market. Jon Wertheim explores the phenomenon that has become a booming international business and a key part of the World Cup experience. Wild Horses – Sharyn Alfonsi visits the Wyoming Honor Farm, a state-run minimum-security prison in the middle of horse country doing its part to help the wild horse population through a program where inmates train the horses. Federal land managers say the number of wild horses roaming public land is nearly three times what it should be, and if left unchecked, their population can double every five years.