Mary Lynch lives in Sharpestown on the northside of the city in Dublin.She lives with her only son Liam.Then one night a knock on the door all mother's fear.The police tell her that Liam has been attacked on a night out and is badly hurt.Mary goes to the hospital and look's at her son battered and bruised.The local police will not help her get the attackers.The only person on her side is Detective Flynn.Mary promises her son that she will hunt the men that hurt him and get her revenge on them.She will make them suffer just before she kills them slowly.