For a while there, I thought a better title for this book would have been Wyoming Jaws. Page 9 (or so) spoiler: Young Clay Hutmacher, Jr. is out trout fishing in the Twelve Sleep River, thinking about his imminent marriage proposal to (also young) Sheridan Pickett. It is literally the last thing on his mind, as his skull gets crushed by an attacking grizzly bear who's developed a fearless animosity to human invaders.
Obviously, a job for game warden Joe Pickett. (Do I need to explain that Sheridan is Joe's daughter? If so, stop reading this right now, get a copy of Open Season, start reading.) But that's not all: it turns out that one of Joe's surviving former nemeses, Dallas Cates, is being released from the Wyoming State Pen. Which is a dreadful mistake, but them's the rules. Cates is looking for revenge on the people who (he thinks) did him wrong. That includes Joe, Nate Romanowski, their families and friends, … Cates is picked up by a pathetic convict-groupie, and also (unexpectedly!) teams up with a different Joe-nemesis from a previous book.
The body count gets pretty high, because Cates and his entourage are as amoral about human life as that grizzly. And they come up with a pretty ingenious (by which I mean: ludicrous) plan to divert blame from their trail of carnage to that rampaging bear.
That body count includes some folks that I am going to miss. And (slight spoiler) there is considerable setup for the next book (books?) in the series. I'm there.