Grace, Annie and Tommy are growing up fast as police officers, but nothing can prepare them for the turmoil they face every day. It’s a year since the fall of the McIntyre crime gang and the vacuum has been filled by rival gangs, all competing for dominance. Constable Shane Bradley is drafted in to help, but his motivations are unclear. Tommy is dangerously seduced by the world of intelligence policing, while Grace struggles to deal with her son’s absence, and growing feelings for fellow officer Stevie. As a young loyalist threatens to take over the city, the officers face a major gangland feud – culminating in a violent and devastating confrontation.

　　三名北爱尔兰首府贝尔法斯特的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？

北爱共和军领导人鲍比•桑兹（迈克尔•法斯宾德 Michael Fassbender 饰）因为领导反对当局的游行而被捕。在梅兹监狱中，他依然没有放弃斗争。监狱里都是六平方米的封闭牢房，这里关押着北爱共和军的囚犯，他们赤身裸体拒绝穿囚衣，以此对抗撒切尔夫人剥夺囚犯权利的法令。他们用污浊的食物和排泄物掩盖着变形门下的沟渠，以此传递消息。
通过一台蒙混过关的收音机，囚犯们得以及时了解共和军与英国政府斗争的消息。最后，在桑兹决定以绝食抗争的时候，他与神父多米尼克•莫朗（利亚姆•坎宁安 Liam Cunningham 饰）有过一场精彩的辩论，然而结果却于事无补……
本片获得第61届戛纳电影节金摄影机奖