Jack Reacher breaks a bully's nose and finger after being repeatedly provoked in a Texas saloon, so when the bully turns out to be a local cop and shows up with three of his colleagues the following day to arrest him, Reacher decides it's time to move on. He chooses hitchhiking as the fastest escape and hooks up with a driver of Mexican heritage named Carmen Greer. She says that the only reason she stopped, however, is because she has a problem: Her tax-evading husband, Sloop, is coming out of prison soon, and he will inevitably continue beating her as he did so many times before, especially because he knows she was the one who informed on him. Carmen has been diligently searching for candidates to kill him, and she thinks Reacher's military background may qualify him for the job. Reacher initially refuses and even leaps out of the car and back into the sweltering 110-degree (Fahrenheit) heat, but then he expeditiously changes his mind and agrees to accept a ride back to her ranch. It is there that Carmen, her husband Sloop and the rest of his family live, and Reacher is promising nothing more than to look into the situation and, if necessary, to act as her bodyguard.
Child wanted Carmen Greer to appear as a character whom readers would not know whether or not to trust. He has also said how he wanted Alice Amanda Aaron, the Harvard educated, vegetarian, lesbian, attorney Reacher hires, to be a reflection of how diverse America is; he can be quoted as saying "she's totally normal in New York, but a freak in Texas.