This is an interesting and haunting book that basically goes to a pivotal point in history and examines what world we would be living in if that outcome had changed. This is the best 'alternative history' book that I have read. This book is thorough and long, but it goes quickly. I found that I needed to take breaks from reading it to fully digest what was going on in the book. I think history lovers will love it; I could find no errors in the facts. But, anyone who enjoys a good thriller will like this book. There was nothing in the book that triggered nightmares for me. It has a dash of Science Fiction, Time Travel, and Techno-Thriller. I received an Advanced Review Copy for free from the publisher via Bookish First and this is my honest review.