Roger Carstens' work over the last five years as the special envoy for hostage affairs has led to the release of American hostages held by other countries. He was also part of the team that negotiated Brittney Griner’s freedom and a complex deal that led to the release of Evan Gershkovich, Alsu Kurmasheva and Paul Whelan from Russia. Amna Nawaz sat down with Carstens to discuss his efforts.