I loved this chilling and intriguing mystery featuring our favorite FBI agent Pendergast. I enjoyed the historical mystery meets present day. This book features one of my favorite characters of the series, Nora Kelly. I was excited when I found out that there is a spin-off series featuring her. I'd highly recommend reading Thunderhead before this one which introduces us to Nora Kelly and shows her first meeting with Bill Smithback. It's strictly not required as this one gives us enough information to make sense of their backstory but its just a really good book so worth checking out if you love adventure stories. I liked the twists and turns in this one and even though I've read it multiple times I still find the end mindblowing and sets up an excellent storyline to come.