After the end of the conflict in Northern Ireland, paramilitary groups turned into gangs that enforced their own street justice. Their decisions are incontestable and irrevocable. But when a local dog receives a death sentence, it may turn out that this time the thugs are trying to bite off more than they can chew. Quentin Tarantino’s Reservoir Dogs is an innocent child’s play as compared with this perverse gangster cinema with a remarkable awareness of the convention, sense of humour and distance.

该剧讲述北爱尔兰首府贝尔法斯特的一线警事。三名菜鸟警察要为正义而奋斗，却发现他们要对抗的是贩毒集团、准军事组织、卧底特务、当地社区，甚至是自己人。一场大规模的当地犯罪帮派调查行动戛然而止后，重重困难与危险问题随之浮现。是谁在保护这些罪犯？又为何要保护他们呢？

该剧改编自真实事件，一名军情六处的双面间谍和女儿被投毒，与他们同处一个小镇的人都身陷危险之中，警方需要竭尽全力保护他们。