Scott Nolan's life is shattered one wintry Dublin morning when his young wife Laura is brutally murdered on her way to work. Scott, an Irish-American doctor recently moved to Ireland, is devastated, the more so since he quickly realizes that the round of bullets had been aimed at him, as pay-back for his involvement in the government's anti-drug campaign.
Burying his wife doesn't end the nightmare for Scott Nolan. In a desperate attempt to claim back his life and find the man who killed his wife, Scott enters into an uneasy alliance with Laura's brother, Detective Mark Higgins. Together they begin to slowly and systematically infiltrate the drug scene. Snatching criminals and dealers from the street, they administer interrogation narcotics to gather intelligence, compile names and search for the weak link in the intricate network of the Irish drug cartel. Bit by bit, a target emerges: Sean Kennedy, a cold and ruthless killer who together with Patrick Mulligan, an ex-drug squad detective, is now in the final stages of an operation, which would set the pair up for life.