刚刚下班回来的林潇潇有点不淡定了，因为她听到了卧室里的男友在接听女人的电话，打电话的女人不是别人，而是男友的上司。明知男友是在和上司交接工作，但自己也是心生醋意。男友陈泽言发现女友的不对劲，简单聊了几句就匆匆挂断电话。为了弄清马素对自己男友有没有爱慕之意，林潇潇决定跟踪男友，通过网络渠道，她找到一名有经验的私家侦探跟踪男友。她完全不知，私家侦探就是男友上司安排的，原来林潇潇的一切，都在马素的掌握之中。在马素的精心安排之下，侦探教唆林潇潇策划了一场假绑架，目的就是为了试探陈泽言的真心，林潇潇欣然答应。最终陈泽言与林潇潇执着的爱情打动了马素，在马素的操办下，陈泽言向林潇潇求婚成功。
学古典音乐的孟晓星（陈奕迅 饰）遇见大提琴手林霏（顾绍华 饰），随即被其高雅的气质所吸引，但林霏不为所动。林父（濮存昕 饰）对女儿宣布再婚，失意的林霏到酒吧借酒浇愁，不料酒中被人下药，糊里糊涂与晓星发生了关系，数日后被医院查出己患爱滋，室友得知后逃也似的搬离。晓星知道林霏的病是他所传染后异常悔恨，但他体检的结果却是HIV呈阴性，为了安慰林霏，他没有将真相告诉她。林父为给女儿筹集治疗费，增加了一份兼职工作。其实真正把病传染给林霏的是与之有过一夜情的高强（徐僧 饰），而高强却认为是林霏害了自己......
As Leo's replacement Thomas Chamberlain arrives Nikki investigates the murders of Rachel Freedman, shot in the head, and her little autistic son Nathan, who was poisoned. Nikki rejects policewoman Anne Burchett's theory that Rachel killed them both but is perturbed when an impostor, claiming to be Rachel's sister, visits the morgue. At the same time the disfigured corpse of Eva Liron is discovered, killed with the same poison as Nathan. She had been the nanny to French hot shot footballer Isaac Dreyfus and was planning to blackmail him over a sex tape of them both. Jewish Isaac is a controversial figure due to his anti-Muslim sentiments but he denies ant part in the murders. Then another victim, Isaac's agent Mousa, is discovered dead.
风雪之夜，叶诗颖和母亲玉琴踏上了最后一班开往北京的夜车，望着车窗外满天的风雪和驾车一路追来的父亲叶志刚，母女二人沉默无语，一段两代人的情感故事也就此展开……
