Who was Friedrich-Wilhelm Krger? An idealistic German officer who entered World War I at the age of twenty. A soldier who experienced the dishonor of defeat. A man appointed to head occupied Poland in 1939, serving Adolf Hitler. An executioner whose major role in the extermination of two million Polish Jews had not previously been explained by historians. The supreme head of the SS, who built the camps of Beec, Sobibr, and Treblinka and coordinated the destruction of the Warsaw Ghetto. How could this enthusiastic young man become, in two decades, one of the worst executioners of World War II?

In this captivating biography, Nicolas Patin uses Krger’s rediscovered diary and German, Polish, and American archives to reconstruct the journey of an ordinary executioner, shaped by thirty years of violence from one war to another.