在这部探案新窍门 第六季剧情/喜剧/犯罪片中,BBC的关于大都会警察局“悬疑旧案”部门的喜剧。小组的头是女DS桑德拉普尔曼，既然是和旧事有关，索性就招聘了3个退休侦探：杰克把死去的爱妻埋在后院每天和她聊天，盖里年轻时有名的花心如今要和三个前妻四个女儿共进晚餐，布莱恩是个强迫症、前酒徒和阴谋论者。标题取自一句老话：“You can't teach meijubar.net an old dog new tricks（老家伙学不来新窍门）”。这帮老家伙却成功地在新时代用他们的经验和技，那些疑难案件正中了看似过时的老窍门的道。
Having lapsed into alcoholism, Brian is booked into a rehabilitation clinic run by an order of monks. A chance remark by Father Bernard leads Brian to telephone Sandra late at night to tell her that there was an unexplained death in the clinic nine years previously. To prevent Brian obsessively investigating by himself, the team take up the enquiry into the death of a heroin addict, and infiltrate Gerry into the clinic as a compulsive sex addict. Brian's wife Esther discovers the whole team at the clinic, and is furious, but Sandra persuades her that it is the only way to ease the strain on Brian. By the time Gerry's cover has been blown, the team have discovered that the dead man, Robert Smith, probably took to drugs as a result of post-traumatic stress disorder, after witnessing or even participating in events in the civil wars which followed the break-up of Yugoslavia. They also discover that some of the staff and even the monks at the rehabilitation centre have secrets they wish ...
