Dave Boyle (Time Robbins), Sean Devine (Kevin Bacon) and Jimmy Markum (Sean Penn) are childhood friends from a blue-collar Boston neighborhood. One day, in the summer of 1975, Dave Boyle was kidnapped and molested for several days. Now the three boys are all grown up. Sean is a homicide detective. Jimmy is the father of three children, Katie, Nadine and Sara. And Dave is still trying to come to terms with what happened to him as a child and protecting his son from any harm. When Katie Markum (Emmy Rossum) is murdered, Sean is assigned the case. Jimmy swears to find the killer before the cops and take care of situation himself. And Dave ends up being a suspect. Now Sean has to solve a murder involving both his best friends from childhood before Jimmy does something he'll regret.