Rookie PTU officers Fan and Fat manages to find themselves in a shootout with fugitives but ends up in a favorable light afterwards, earning promotions to CID officers.

Inspector General Li Tiezhu took over the investigation of a case related to the collusion between police officers and the underworld. The target figures were Huang Zhenxiong, the detective of the serious crime team, and a group of agents under him. Xiong solved many cases with the help of the underworld, but he also accepted the benefits of the underworld and had illegal discipline. Li Tiezhu wanted to collect evidence of Xiong and others, but because Xiong was also a competent policeman and was good at hiding evidence to avoid legal sanctions, Li Yi could not bring Xiong to justice for a while. After that, a new captain named Chang joined the ranks of Xiong. Chang was an upright policeman. Xiong's attempt to buy failed, and Li also took the opportunity to use Chang to collect evidence of Xiong's crime to arrest Xiong, and Xiong committed suicide in fear of crime.

屯门屋出现色魔，相继发生奸杀案，犯案手法变态残忍，屯门居民人心惶惶，李SIR与其属下备受压力，务必将色魔绳之于法。众探员四处调查，以女警为饵，引出色情狂忠。正当警方毫无头绪时，又有一名少女被杀害，原来色魔近在眼前，正是警署冷气技工"威"，"威"性欲过旺，其妻无法应付所需，故"威"四处寻找猎物。惜在过往案件中，"威"都能不留痕迹，根本难以入罪。将经李SIR分析下，终于寻得"威"每次做案后用作烧衣服之火盆，并证明火盆上的衣服纤维，与死者衣服所染有的相同，成为有力证据!终于将"威"定罪。

翁玉（李美凤 饰）本来生活在一个幸福的家庭之中，丈夫阿森（黄秋生 饰）年轻有为，儿子活泼可爱。然而，不幸的是，阿森竟然拥有性虐待的癖好，每晚，翁玉都要面对来自丈夫的惨无人道的羞辱和折磨。翁玉的母亲身患顽疾，唯有阿森能够得到治病的良药，因此翁玉只能默默忍受前者的暴力。 某日，忍无可忍的翁玉第一次反抗了阿森，两人追打至街角，遇见了刚好路过此地的探员阿雄（李修贤 饰）。阿雄十分同情翁玉的遭遇，之后将翁玉和她的儿子藏在了女友珍妮家中。哪知道阿森找到了翁玉的母亲，以此要挟妻子现身，他打算带着妻子和孩子同归于尽。

孟波（周文健 饰）曾经是飞虎队中的一员，精明强干的他身手矫健，然而，一场意外让他丢掉了工作，流落街头。阿雪的父亲是黑帮老大，一直不满父亲的“职业”，叛逆的阿雪决定离家出走，阿雪的父亲委托孟波暗中保护阿雪，面对老大的女儿，孟波不敢有任何非分之想。 阿雪一直想让父亲金盆洗手，为此不惜想出种种计划，闹了不少的笑话，与此同时，帮派中，二叔一直觊觎阿雪父亲的位置，想要除掉阿雪的父亲，成为老大。他先是重金聘请了职业杀手暗杀阿雪父亲，被孟波阻止后又伙同飞虎队队长及一干队员绑架了阿雪和其父亲。面对来势汹汹的敌人，孟波所剩的时间不多了。