本季故事从罗宾（寇碧·史莫德斯 Cobie Smulders 饰）和巴尼（尼尔·帕特里克·哈里斯 Neil Patrick Harris 饰）的婚礼说起。时间回到2012的夏天，不装这是个充满爱的季节。巴尼和女友奎因，不装泰德（乔什·拉德诺 Josh Radnor 饰）和女友维多利亚，罗宾和男友尼克，以及马修（杰森·席格尔 Jason Segel 饰）、莉莉（艾丽森·汉妮根 Alyson Hannigan 饰）和儿子一家三口，每个人都非常幸福。马修夫妇忙于照料孩子，其他三对情侣和和美美。然而10月份一到，他们就迎来了传说中的“分手季”。经过一番折腾，巴尼和奎因分手了。不久后，泰德和维多利亚也因为一个不可调和的原因分手了。随后，巴尼宣布和罗宾订婚，这究竟什么怎么一回事……
回复 :Set during Christmas 1988, Lol is haunted by the devastating events that took place two and a half years before. She and Woody both find themselves struggling to cope with their lives without each other after he leaves the gang. Lol is carrying the burden of her guilt, whilst Woody is trying to build a domestic life with a new girlfriend and a potential promotion at work. Shaun has started drama college and, although still in a relationship with Smell, he has grown close to a girl performing in his Christmas play.
回复 :围绕因父亲的死得知自己是被收养的孤儿的事实后，也坚持留下来照顾家人的李秀晶(李素妍 饰)而展开，该剧将带给观众感动与温馨。
回复 :一場意外的悬案令警队实习生穿越到李元芳身上，开局就要被斩首？！命悬一线之际，只听远方有人喊，”刀下留人“！
