The husband and wife team of Serge and Beate Klarsfeld worked tirelessly to have Nazi war criminal Klaus Barbie extradited from Bolvia to stand trail in France. Barbie known as "The Butcher of Lyon" was responsible for the deaths of 10,000 French Jews.

A half-century after the war, American journalists track down former Gestapo officer Erich Priebke, allegedly responsible for some of Italy's worst atrocities who fled to Argentina after the war.

How Mossad agents from Israel spent nearly thirty years tracking the notorious Nazi physician Josef Mengele.