Dead Men(2008)

Stephen Leather

Undercover cop Dan "Spider" Shepherd knows there are no easy solutions in the war against terrorism. When a killer starts to target pardoned IRA terrorists, Shepherd must put his life on the line to protect his former enemies. While he is undercover in Belfast, a grief-stricken Saudi whose two sons died under torture in the name of the War on Terror is planning to avenge their deaths by striking out at two people close to Shepherd. As the assassin closes in on his prey, Shepherd realizes that the only way to save lives is to become a killer himself.