November, 1950. A force of US Marines, US Army troops, and British commandos find themselves cornered around a remote mountain lake deep in North Korea. With over 100,000 Communist Chinese troops bearing down on them, victory is no longer a possibility, but escape just might be. But can they make it? In our second episode, follow the frantic retreat, the desperate fighting, and the clamor for survival, from the most daunting peaks to the most treacherous valleys of South Hamgyong Province, one map at a time. This is the defining battle of the Korean War. This is the Chosin Reservoir.