Knee-deep in snow, and under a leaden sky, American Marines thousands of miles from home watched more snow settle onto the frozen ground, glittering in the fading light. Suddenly, the still Korean night roared to life with the sound of Chinese mortar fire. The Fifth and Seventh Marine Regiments were besieged and surrounded by the Chinese 9th Army Group in a surprise attack at Chosin Reservoir in what is now North Korea. Vastly outnumbered and outgunned, defeat and death seemed guaranteed. Their improbable escape after a week of brutal combat required all the Marines' fighting skills and supreme combat leadership.