World leaders are meeting at the annual U.N. General Assembly against a grim backdrop of global conflict and deepening geopolitical divisions. In the Middle East, war conditions are escalating. Lebanon reports a death toll of at least 274 on the deadliest day since the 2006 war, after Israel conducted extensive airstrikes on Hezbollah targets across the country. Talks aimed at ending the war in Gaza are at a standstill. Yet diplomacy can sometimes yield results. One year ago, Siamak Namazi was released from Iran's notorious Evin Prison in a hostage-prisoner swap with the United States. His was the longest period of imprisonment of any American in Iran -- a horrifying eight-year ordeal. Six months before his release, Namazi bravely called in to this program from inside Evin to make an emotional appeal to President Biden. One year later he is ready to talk for the first time, in an exclusive with Christiane in New York.

Originally aired on September 23, 2024