Tripwire (Jack Reacher, Bk.3)

Ex military policeman Jack Reacher is enjoying the lazy anonymity of Key West when a stranger shows up asking for him. He’s got a lot of questions. Reacher does too, especially after the guy turns up dead. The answers lead Reacher on a cold trail back to New York, to the tenuous confidence of an alluring woman, and the dangerous corners of his own past.