Killing Floor is the first novel in the Jack Reacher series by author Lee Child. Jack Reacher has had enough of Army life and is six months mustered out travelling the US a country he has never seen. Wandering into a small town in Georgia he's immediately arrested for murder. Sent to jail overnight he's put into general population instead of holding, where he's supposed to be and someone tries to kill him. Once he's finally released he learns that the dead guy was his brother and sets out to investigate leading him to look into a powerful local family called the Kilner's and a whole lot of trouble.
The plot may seem a bit far fetched.