We learn so much about Paul Boles in the first few chapters. He seems brutally honest about his obsessive lifestyle, constantly thinking about the FBI investigations into horrific crimes. It cost him his two families because he couldn't pay attention to personal relationships, being a kind of ghost when he was at home. But he was a very successful investigator in many, many cases, including high profile ones like the Golden State Killer. The details about the crimes were often more than I wanted to read. But this look into real life crime fighting, as opposed to that which we see on our televisions, is significant, if a bit overwhelming.