This was a really engaging spy thriller with one heck of a twist ending! It kept me hooked from early on and, even though I don't usually gravitate towards spy thrillers, I really had trouble putting it down. The writing style is very easy to digest, yet compelling, and I never felt that I was confused even when they were explaining CIA back-channel hacking and things like that. 

Even though the subject was not an original idea, the author was able to breathe new life into the spy genre by taking things from a slightly different angle and I really enjoyed this read!