The true story of a father and son's fight to stay together and to survive the Holocaust. In 1939, Gustav Kleinmann, a Jewish upholsterer in Vienna, was seized by the Nazis. Along with his teenage son, Fritz, he was sent to Buchenwald in Germany. When Gustav was set to be transferred to Auschwitz, Fritz refused to leave his side. Throughout the horrors they witnessed and the suffering they endured, there was one constant that kept them alive: the love between father and son. Based on Gustav's secret diary and meticulous archive research.