There are a few tidbits in this book that offer more information than can be found in news articles, but mostly the book is speculative, exploitative, and short on real insight. The authors quote "experts" who never met the principles but only reviewed media reports, use psychobabble about long-debunked theories of psychopathology and human development, interview people peripheral to the events with lots of speculation and few verifiable facts, distort what facts they do gather to spin conspiracy theories, take a few generalizations in a psychic's otherwise totally erroneous prediction and seem to offer them as proof of something, imply the victims are at least partly to blame for the crimes, and generally practice really poor true-crime writing. Add to these many problems writing as awkward as "Long before Wolfgang the master pupated from Wolfgang the servant" and you have a really distasteful book. Don't waste your money or time.