该剧讲述了“程浩”和“陆鸿渐”双男主在平行空间互换身份，与迷妹林小小所发生的故事。
James Purefoy stars as William Travers, a criminal barrister who is recovering from a traumatic series of events that have shaken his belief in the legal system. On the surface, Travers is a picture of success; an accomplished criminal barrister happily living with his wife (played by Dervla Kirwan) in rural Suffolk. However, Travers is still recovering from events in his past when he is drawn into a case that involves his old friend Martin Newall (Nathaniel Parker), who faces conspiracy and murder charges while at the same time being investigated by a vicious and vengeful detective DS Mark Wenborn (Creed Miles). The five-part series from acclaimed writer Anthony Horowitz (Collision, Foyle's War) is a story of friendship, conspiracy, betrayal and murder as well as a critical look at the way the legal system operates.
何奇通（郭蔼明饰）是“奇通私家侦探社”的负责人，在一次帮助一名女子搜集她的警察丈夫出轨的证据时，与警察耀祖（郭晋安饰）相遇了。耀祖处处帮助同事掩饰婚外情，令到奇通对他这种臭男人十分讨厌，认为他也是一路货色。奇通的父亲在她小时候就是因婚外情出走，留下母亲郁郁而终，而奇通也只得在侦探社负责人德叔（秦沛饰）的照料下长大，所以奇通生平最痛恨出轨的男人。终于奇通完成了任务搜集够了证据，却与耀祖结下了梁子。随后，奇通重遇了中学好友宝怡（汤宝如饰），更得知宝怡竟是耀祖女友，奇通处处提醒宝怡要提防耀祖，更教她跟踪术，搞得耀祖不胜其烦。一次耀祖因工作需要出入色情场所被奇通拍下了照片，阿怡拿着照片想耀祖质问，令耀祖工作受到了影响，自此他更是讨厌奇通。随后阿怡怀上了身孕，准备和耀祖结婚，岂料结婚当日阿怡却突然失踪了。深爱阿怡的耀祖四出寻找，最后因旷工多日被开除出警队。奇通可怜耀祖，觉得自己对他搞成这样也负有一定责任，于是通过德叔邀请耀祖加入他们的侦探社，耀祖一方面想找回未婚妻，一方面迫于生活压力，最终加入了侦探社。于是，他们开始了一段又一段情事缉私档案。
