A strong 4.5, rounded up to 5. Really a top-notch effort by Patterson and his co-author Maxine Paetro. (She also co-wrote many of the Women's Murder Club books, which I also really enjoyed.) I really have a hard time coming up with anything negative to say; the writing is strong, especially the dialog; the characters are solid and complex; the whodunits and why-dun-its are well thought out and well-hidden - that is to say, I didn't have this one figured out well before the story was over.
I like the concept of an ensemble cast; even though Jack Morgan is the head of the agency, and the main character (and the only one with first-person dialog), the other members of his staff are well-rounded, realistic characters. I can see any one of them being the central character in future books in the series.
There have been other of Patterson's series where, after reading the first book, I've vowed not to read any more; this book actually has me looking forward to reading the rest of the series.
(Read as part of our "Reading with Karen" project. I can't say whether she would have liked this one, but it would have been interesting to talk to her about it