Johnson has built a solid following for Sheriff Walt Longmire of Absaroka County, Wyoming. With his best friend, Henry Standing Bear, acerbic undersheriff Victoria Moretti and an assortment of colorful deputies and office personnel, Walt patrols his county judiciously, tending to the small incidents and sometimes larger crimes that are common to his neck of the woods. When a local lady confides that an “angel” is repairing various things around her home, Longmire decides to check it out. What he finds is a young runaway who has come to town looking for his missing mother.
The boy’s name is Cord Lynear, one of the Lost Boys taken in by the Apostolic Church of the Lamb of God. Cord declares that he has a bodyguard, an elderly man who claims to be Orrin Porter Rockwell, whom records report to be two hundred years old. Unwilling to take either of them at face value, Walt does begin a search for Cord’s mother, stumbling upon a gated religious compound new to the area and run by 400-pound polygamist Roy Lynear—the Apostolic Church of the Lamb of God. One thing leads to another, Walt getting a bad feeling about the religious group and the number of weapons-bearing followers around Lynear. Clearly something is afoot behind the locked gates, and clearly the church members have no intention of letting Longmire interfere with whatever they are doing.
Slow to anger and unafraid of confrontation, Longmire sticks closer to home in this mystery except for a few forays to other counties to compare notes on the activities of the church. His deputies watch over Cord and his bodyguard, while Walt, Victoria and Henry Standing Bear roam the county trying to put the pieces together and figure out just what these well-armed folks are up to. The sharp-tongued Moretti is in fine form (and unwilling to curtail her language or suspicion of the newcomers) the action heating up after an act of violence and wanton destruction.
The usually laid-back sheriff is pushed to the limits in this thriller, forced to stop illegal activity that even he hasn’t completely figured out. With Moretti and Henry as backup, Walt takes on a whole compound in a fiery standoff with a dramatic climax. While the lighthearted moments and easy humor remain consistent and Walt and Vic approach rapport on the romantic front, the scheme of the newcomers is contemporary in scope, keeping the tale grounded in reality. Longmire reveals more about himself in A Serpent's Tooth, draws closer to admitting his attraction to Moretti and suffers the outrage of an attack on his department. In spite of his years (past the age of retirement), when the situation calls for action, Longmire is at the front of the charge.