Falling Glass by Adrian McKinty

“Killian makes a living enforcing other people’s laws, collecting debts, dealing out threats and finding people who do not wish to be found. But when Richard Coulter, an Irishman with political connections, offers him half a million to track down his ex-wife and children, Killian finds himself embroiled in something far bigger than he bargained for.”

I was drawn in by his humanity when he realizes the real objective of Coulter and decides to take matters into his own hands.