Vail arrives in Washington to take Kate to an embassy party, however, Kate thought she had made it clear before hand that they were not dating any more. Not that any of it matters now as Kate is called away for work. While Vail may not like working for the FBI he does like Kate, so he decides to tag along, but the case has Vail written all over it. Reluctant to help out once again because of the FBI management system Vail becomes coerced by the director to help, and the case intrigues Vail as well. A Russian embassy staffer code named Calculus is prepared to release the FBI the names of Russian spies/moles within the American government but if the FBI thought that is would be a simple matter of him turning over the names, they thought wrong. Calculus has been ushered back to Russia and has left a string of clues that need to be followed in order to discover the spies. But as each clue reveals itself and all agencies of government are affected as well as the Russian appearing to be one step ahead of them to eliminate their informants. Kate and Vail have no idea who they can trust and what dangerous situation the clues will lead them next.
Boyd grads the readers attention right off that you do not want the book to let go, as it starts off with a bang and continues from there. This book has more mystery, problem solving and code cracking than the first one. There is probably a few less action scenes because of the slight shift in how the storyline plays out when compared to the first book, however, you do not really notice as the body count still seems the pile up. I like the idea about the Russia vs the United States. I mean who doesn't like an old enemy reappearing and reaffirming that everyone is still trying to spy and one up all the other countries.
I appreciated that Boyd took time to develop Vail more as a character, than just sticking with this is how Vail works and why he works that way is a mystery. We get a picture of what Vail's life was like when he was growing up, and it was not completely a pretty picture, but it does help explain part of the reason for not getting along with authority figures and why he prefers a one man team when on the case. It helps put Vail in a more vulnerable role, that along with his own Ego getting the better of him and underestimating the people around him, teaches Vail a little bit of humility. We also get some incite to Vail's sculptures and what they represent to him and why does not let people see them. The one aspect that I found a bit trying was the finding of more information or spies or clues near the end seemed to be forced, this is intertwined with Vail's personality and having to dog everything to the end, it just seemed like enough already, wrap it up. I think this type became a Spy vs Spy battle that never seemed like it was going to end (did I just date myself there???).
Kate does not experience as much growth as a character when compared to Vail, even after the suicide incident. While I enjoy the interaction between Vail and Kate, I found that Kate did not make as many strides as a character as Vail did. Kate is still the woman who is dedicated to her job no matter what. She seems determined to help Vail change and open up, but is unwilling to do it herself. I wish in this book the characters could have grown together.
Boyd has found the right mix of mystery, suspense and action which has created a well rounded novel that I think will attracts people who do not normally read this type of genre, there is really something for everyone in this book (well maybe not the paranormal fans, but people need to read something out of their own comfort zone every once and awhile). Agent X is a solid squeal to The Bricklayer. With a fast past and mysterious story line and some action adventure in there too, I think anyone who is looking for a good read, had better start reading Boyd's Vail series, as the reader will be entertained throughout.