Gitta Sereny is a great author, and this book is a good showcase of her efforts. This is the culmination of over seventy hours of interviews with Franz Stangl, the commandant of Treblinka. This was a very interesting book. I think it is so important to read and listen to things from the perspectives of these former Nazis. It has always made me so curious how people fall into behaviors like this, committing mass genocide and acts of torture and brutality. I really enjoyed this book, and would recommend it.