重案组布网围剿国际毒枭,突然杀出一组蒙面悍匪“黑吃黑”,更冷血屠杀众警察。重案组督察张崇邦(甄子丹 饰)亲睹战友被杀,深入追查发现,悍匪首领竟是昔日战友邱刚敖(谢霆锋 饰)。原来敖也曾是警队明日之星,而将敖推向罪恶深渊的人,却正是邦。宿命令二人再次纠缠,一切恩怨张崇邦如何作出了断……Shan \"Donnie YEN\" is a righteous cop who's is admired by the police force to have solved many cases. One day, his past comes back to haunt him when his sting operation is attacked by a mysterious group of criminals led by Ngo \"Nicholas TSE\", his former protégé. Ngo was once a talented cop who admired and respected Shan. However, a terrible accident sent him to prison three years ago turning him into a furious man with the aim to kill everyone who wronged him - including his former mentor.