江湖傳聞，有人要暗殺管理幫會巨款的龍老四。龍老四著令養兵千日的「御林軍」暗中保護自己及負起殺敵任務，眼見對手一個一個被殲滅，卻發現隱藏更重大的陰謀。

龙老四是黑道大哥，秘密鲸吞了一亿二千万的公款，准备和情投意合的小三阿姗私奔到国外。此事，引起了帮派四大天王的内斗，并引发血案。米探长奉命调查，但这人生性胆小，敷衍了事。帮派元老柴叔和小字辈发仔目睹了这一切，觉得蹊跷，怀疑事出有因。发仔的恋人小玲总是提心吊胆，生怕他出事，劝他不要介入。仅剩的天王怀疑龙老四才是幕后主使人，因此派手下前去调查，杀害了发仔的朋友。其弟跑来劝发仔躲避，不幸丧命，小玲也被误杀。发仔愤怒之极，此时抚养柴叔也卷入此案，发仔奋力营救，两人才逃出魔爪。龙老四私奔未成，遭到老婆与养子Peter仔暗算。危急时刻，柴叔与发仔正好杀到，由此引出一段鲜为人知的江湖隐情…

As befits a full-blooded Jiang Hu (underworld) antic, COTL takes place over the course of a short, frenetic period, feeling to all intents and purposes like one night. It encompasses plenty of gore and cadavers (unless you get the sanitized, inferior mainland version), relying to a large extent on so-called triad codes of honor and organizational culture. At its core resides old boss Dragon Brother, done by Eric Tsang in a repast from his barrage of comical roles and commercial endorsements. The head wants to retire, leading to chaos in gangland as everybody else desires his position and accumulated fortune. Following his fateful announcement, two rival Mafioso's become potential enemies as Dragon Brother and concubine (Suki Kwan) aim to leave Hong Kong in order to start a new life in Europe.

Tăng Chí Vĩ và Dư Văn Nhạc diễn xuất trong bộ phim về thế giới mafia trong cuộc chiến giữa lòng trung thành và sự phản bội.