While in Chicago, Jack Reacher is helping out a young woman with an injured leg with her dry cleaning when they are captured at gunpoint by three men and thrown into a car, then transferred into a van and driven cross-country.

On the way, Reacher learns the woman is an FBI agent named Holly Johnson, though she does not tell him she is the daughter of the Chairman of the Joint Chiefs of Staff and goddaughter of the President, having been accused of being the beneficiary of nepotism all her life.

The Chicago field office where Holly worked takes charge, with only Agent-in-Charge Paul "Mack" McGrath and two others, Milosevic and Brogan, involved.

Reacher and Holly finally arrive at their destination: a mountain community that's home to a radical militia wishing to secede from the United States.

Holly, intended by leader Beau Borken to be used as leverage to make her father agree to his demands, is placed in an upstairs room of an abandoned county courthouse, whose walls are supposedly filled with dynamite.

When the President, fearing political fallout from a bloodbath, refuses to authorize an attack, McGrath and his men go rogue, setting up camp near the compound.

As the FBI round up the remaining militia members and demolish the compound, Reacher discovers that Holly's cabin is not actually filled with dynamite and realizes that Borken sent Stevie, the last surviving kidnapper, to San Francisco to detonate it in the middle of a Fourth of July celebration.