In the closing weeks of World War II, advancing Allied armies uncovered the horror of the Nazi concentration camps. The first camp to be liberated in western Germany was Buchenwald, on April 11, 1945. Within days, a special team of German-speaking intelligence officers from the U.S. Army was dispatched to Buchenwald to interview the prisoners there. In the short time available to them before the inmates' final release from the camp, this team was...