The Innocent by David Baldacci

Will Robie is a hitman for the government. He's always followed orders in the past. But now his target is a single mom and something seems fishy to him. So he refuses to kill the woman. Unfortunately, someone else does. And Will realizes he now has a big target on his back. When he gets on a bus to hightail it out of town, he notices a man getting ready to kill a teenage girl. He stops him and gets her off the bus--just before it explodes. Now he and the girl Julie are on the run together, unsure whether the explosion was meant for him--or her. So begins the never-a-dull-moment Innocent by David Baldacci. Both Will (the loner who suddenly feels responsible for the safety of a 14 year old) and Julie (the very bright and stubborn 14 year old) are appealing characters, as is feisty FBI agent, Nikki Vance. There's lots of good paranoia (Whom can we really trust?) and plenty of plot twists. All in all, The Innocent is a pleasant way to spend a lazy weekend.