本剧由四宗发生在香港扣人心弦的真实刑案带出四个令人惊惧的罪行藉由一队重案组的警探办案实录贯穿而成包括耸人听闻的「屯门色魔强奸案」喧腾一时的桃色纠纷「溶尸案」使市民提心吊胆的「大圈仔军火械劫案」及「淫业大厦扫黄行动」案件生动地描绘各阶层犯罪的人性丑恶而编剧为了加强剧中人物与案件的关连性特别穿插男女主角CID张兆军林嘉华女CID丁兰蓝洁瑛重案组总督察方伟陶大宇扫黄组女总督察刘婉仪梁婉静及聂志华张国强一段微妙的五角感情关系交错编织成属于都市人性化的实录档案
Six months have passed since Dr Ogden moved to Buffalo and Det Murdoch is constantly a loggerheads with Dr Francis, her replacement While Insp Brackenreid thinks highly of Francis, who was recruited from Scotland Yard, Murdoch finds him stubborn and unimaginative He also seems to be in no rush to help Murdoch with his latest case where human body body parts were discovered on a riverbank encased in cement A homeless man living in the woods nearby is questioned and released and Murdoch corresponds with Dr Ogden who offers him valuable advice in her letters He also gets help from a retired detective, Malcolm Lamb Murdoch connects his current investigation a rape and murder that had occurred many years before
