Very interesting book. If you've read From Hell, and you want to know a bit more about where Moore got his ideas, this is the book to read. There are a few leaps, I think, as far as Knight's conclusions, but for the most part, he does a very good job of investigation. It's the only non-fiction book I've read on the Ripper murders, and I can't say I know anything of developments since From Hell was written, but it has peaked my interest and I plan on continuing to learn about the subject. The most amazing part of this book is the final chapter, which, while it answered the biggest question on my mind while reading the book, I still didn't really see it coming. It's a major detail that Moore left out of From Hell, though I'm not sure why. A very good read.