曾经在黑道中呼风唤雨的发哥（吴镇宇 饰）在挨过了漫漫十六年的牢狱之灾后终于重获自由，然而，刚刚出狱没多久，发哥便决定着手实施他在狱中早已经设计好的惊天劫案。于是，机械高手丧宝（任达华 饰）、造型师杜公子（谭耀文 饰）、飞车辣手林东（郑浩南 饰），这些昔日弟兄们重新聚首，将目标放到了一辆运送黑钱的运尸车上。 徐安良（古巨基 饰）是一名警员，恪尽职守的他敏感地发现了发哥的计划，尽管没有得到上级的批准，但他还是决定依靠自己的力量将这一帮犯罪分子们一网打尽。就在情势越来越紧张之时，一帮悍匪加入了战局，成为了发哥一行人的“竞争对手”，复杂的情境之下，究竟谁会是最后的赢家呢？Big F, who's just gotten out of prison, wastes no time in tracking down his old comrades, picking up bowling alley employee Crazy B, back-alley hairstylist Johnny T and mechanic East L in quick succession. As it turns out, Big F wants to rob a truck transporting dirty money across the Mainland-Hong Kong border, and to do that, the gang's got to pose as police officers. On the day of the heist, the men set off in their minibus-turned-police-vehicle dressed as cops and armed with BB guns. What they don't know is that another group of criminals also has its sights set on the truck and those people have AK-47s.
