In January 1942, Soviet press photographers came upon a scene like none they had ever documented. That day, they took pictures of the first liberation of a German mass atrocity, where an estimated 7,000 Jews and others were executed at an anti-tank trench near Kerch on the Crimean peninsula. Dmitri Baltermants, a photojournalist working for the Soviet newspaper Izvestiia, took photos that day that would have a long life in shaping the image of Nazi...