Call the Swallow, Fergus O'Connell

David Steinbaum, a Polish Jew, witnessed the horrifying effects of Hitler's campaign against the Jews in Eastern Europe - and yet, 60 years later, he has still not discovered the fate of his sister Ariela, a young jazz singer in pre-war Warsaw.
About the Holocaust, this story unravels the fateful events in the lives of David and Ariela. But there are other forces at work. Rudolf Fest is a family man, with a future in the Gestapo's Department of Statistics. To Rudolf and his colleagues, the lives of Jews are nothing more than numbers on a chart.