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In this one it seems that Nate has been so domesticated with a wife and a new daughter that he's let his guard down and the story keeps you on tenterhooks as his family is stalked by some people seeking revenge for events in the last book. Meanwhile Joe is investigating the long range shooting of a judge's wife. Was she the target or was her husband the target? Joe's investigation is stymied by an incompetent sheriff with his eye on the next big leap in his own career and when the sheriff arrests Nate for the crime the reader knows that that sheriff has sealed his own fate. Alienating Joe and Nate is not usually a good career move for anyone.
This was a very well written story with lots of twists and turns. I really loved it. I particularly loved the cast of characters that turn up at the ending (no spoilers) - it was just a well written scene and just wonderful.