I have read all of the Reacher series, not always in order. But I did start consecutively with numbers 1-5, and I felt that this book really built on the first and elevated Reacher to a new status in action-focused fiction. I can't believe that I - an almost 50 year-old woman - would enjoy reading the details about weapons and military history and combat strategies so much. But, I definitely did. As an author, I really appreciate Mr. Child's ability to make stories appealing to both men and women - a relatively rare skill.
In this book, I also appreciated the presence of a strong female protagonist. Despite being in significant pain during the course of the novel, Holly remained cool-headed, creative, willing to take advice but follow her own direction, capable, determined...wow. That was nice to see in a book with a larger-than-life male lead.
As for Reacher, I think he really comes into his own in this book, and we start to get a glimpse into the components of his make-up. Certainly we see what he's capable of, and we see his ability to isolate emotion (Wait, does he have any? Why, yes. Yes, he does.) when he needs to. He is a soldier at heart - a well-trained, smarter-than average, resourceful and very skilled soldier, but it's at the core of who he is, and that's never lost in the books.
There were some times when a suspension of disbelief was required - the timing of the kidnap, Reacher being kept "in the game" for as long as he was - but that's true in almost any book, and certainly in many in this genre. It was no problem for me, and I thoroughly enjoyed this read. Recommended.