Former paramilitary killer Gerry Fegan wanders New York City, hiding from a past he escaped at terrible cost. But he made a fatal mistake: he spared the life of Bull O'Kane, a ruthless man who wants revenge. Too many witnesses survived a bloody battle at his border farm, and now he wants them silenced, whether man, woman or child. O'Kane calls the Traveller, an assassin without pity or remorse. Back in Belfast, Detective Inspector Jack Lennon, father of one of the witnesses, is caught up in a web of official secrets and lies as he tries to uncover the whereabouts of his daughter. The closer he gets to the truth about the events on O'Kane's farm, the more his superiors instruct him to back off.