In March 1997 Major Jack Reacher walks into the Pentagon for a 12 o'clock appointment. He is wearing his Class A uniform, clean and pressed with all of his medals polished just like his shoes. But he is also wearing five days' growth of beard, and he is looking for the set-up, for the trap, wondering if he will get to keep that appointment.

Five days previously he had been in the office of his own Commanding Officer who was explaining that Reacher would be going undercover this time. A woman had been murdered in a small town in Mississippi. The town, Carter Crossing, is next to an army base, Fort Kelham and the Fort houses two Companies of Army Rangers which fly in and out on a regular basis to Kosovo, but not officially. To make matters worse, one of the Company Commanders is the son of an influential Senator. So all in all care needs to be taken and the investigations into the woman's death closely observed. Things could get difficult should it turn out that the woman's killer is a soldier from the base. The Army doesn't want attention drawn to Fort Kelham.

Wearing anonymous civilian clothes and with a toothbrush in his pocket, Reacher boards a Greyhound bus to Memphis and hitches several rides to Carter Crossing. But there he finds that the facts don't quite match the version given to him by his commanding officer. He also finds a very beautiful Sheriff in charge of the police investigation.

Child's precise descriptions of settings and landscape enable us to accompany Reacher; to see what Reacher sees as he follows the investigation of not just one murder - but three. A rail-road track runs like a spine through the small town of Carter Crossing; it divides west from east, right side from wrong side of the tracks, white from black, civilian from army. The rail-road track also runs like a backbone through the novel, a place of confrontation and death. This is how Child tells us a story, no interior monologues, no purple prose, not much description of feelings and emotions – just close observation of the facts and of the interactions between his characters.

THE AFFAIR is Lee Child's sixteenth Jack Reacher novel, a retrospective one, taking us back to Reacher's life as a US Army military policeman in 1997. As such, it tells us how Reacher's military life ends and he becomes the "wandering samurai" of the previous books in the series.