It was an ordinary-looking photograph. Just the portrait of a man. But the very sight of it chilled Allon to the bone. Art restorer and sometime spy Gabriel Allon is sent to Vienna to authenticate a painting, but the real object of his search becomes something else entirely: to find out the truth about the photograph that has turned his world upside down. It is the face of the unnamed man who brutalized his mother in the last days of World War II, during the Death March from Auschwitz. But is it really the same one? If so, who is he? How did he escape punishment? Where is he now?