海港城北区分局破案王陈在天(周渝民 饰),误跟邱局长的千金上床,而申请调到南区分局工作。在这里,他遇到了性情火爆的拍档吴英雄(赵又廷 饰),后者正在调查毒品dreamer的犯罪团伙。由于陈在天被检验科分析师蓝西英(张钧宁 饰)查出体内含有dreamer成分,而被视为毒物 。加之他平时轻浮放荡的表现,也让吴英雄十分不爽。在办案中,两人结识了三联帮帮主的千金陈琳(陈意涵 饰),三人不打不相识,并在办案中产生感情。在地铁追捕Dreamer罪犯时,陈在天救了陈琳,但后者却认为是吴英雄所为,并对他产生了好感。然而,几次阴差阳错之后,她却慢慢爱上了陈在天。不过,陈在天总是躲闪不敢接受,因为他内心一直纠结于自己的身世之谜。然而,这些人却先后卷入了一场由萨克奇恐怖组织导演的阴谋之中…… 本片获得金钟奖最佳影片、最佳导演,赵又廷凭借此片获封金钟奖视帝。Pi Zi and Ying Xiong are two cops who are as different as day and night. One does nothing except for drinking coffee and living a luxurious lifestyle while waiting for information from dubious sources to crack his cases. Another believes law and justice are the pillars of society and is constantly on the street catching criminals - a little over-zealously for his superior's liking. When a case brought these two top crime-solvers together, sparks flied and a little light peeked into this dark city where the nation's President is on friendly terms with the local triad and twins kill people while drinking milkshake.