This was my first Daniel Silva mystery, but will not be my last! This is the 4th in the Gabriel Allon mystery series, starring Allon, an Israeli intelligence agent. In this mystery, Allon is tracking down a Nazi war criminal who was responsible for hiding the murder of thousands of Jews at Treblinka. The flashbacks to the Holocaust were vividly described and brutal. What I enjoyed about this book is how it really made me reconsider some of my thoughts about the effort placed in bringing Nazi war criminals to justice. When you read about this in the papers, sometimes you have to wonder what the purpose is in chasing down these men who are footsteps away from the grave. Does it really matter? After reading this book, I realize that crimes like these cannot be ignored or forgotten - no statute of limitations for cruelty or genocide. Good story!