安东尼（文森特·林顿 Vincent Lindon饰）和赛波琳娜（玛蒂尔德·塞尼耶 Mathilde Seigner 饰）即将携手步入婚姻的殿堂，赛波琳娜的母亲蕾雅（凯瑟琳·德纳芙 Catherine Deneuve 饰）早年间和丈夫离了婚，之后一直过着自由自在的生活，个性风趣而又开朗的她竟然在女儿女婿的结婚庆祝会上搞起了花样，惹得众人捧腹，她特立独行的风格深深吸引了安东尼。
一晃眼，赛波琳娜的孩子出生了，蕾雅前来探望宝宝，安东尼无法压抑内心里对于蕾雅的感情，向她表白了。为了女儿的幸福，蕾雅当然是狠狠的拒绝了前者。虽然遭到了拒绝，但是安东尼并没有放弃，而是制造各种各样能跟蕾雅独处的机会，向她发起猛烈的攻势。

Husband and wife Ludovic and Karine, and Ludovic's sixteen year old daughter Nelsa lead a relatively carefree life. Motorcycle riding Ludovic, a dance instructor, changes jobs every three years to keep himself interested in whatever he's doing. Ludovic recently remarried, this time to landscape designer Karine, a younger, beautiful woman who regardless is insecure due to her immaturity. Since she doesn't know how to handle that insecurity, Ludovic has placed Karine in various forms of therapy to help her with her life. Nelsa can see the cruelties that life has to offer, and although she doesn't like them, tries to embrace them to expose them for what they are. Ludovic wants to give everybody in his life, including Karine and Nelsa, as much freedom as they need to be happy. Husband and wife Pascal and Marthe and their adolescent son Eric lead a typical middle class life. Pharmaceutical salesman Pascal likes to think of himself as important to bolster his own sense of masculinity, which has led to him being a serial philanderer. Secretary Marthe knows about Pascal's unfaithfulness deep in her heart. The two couples meet when Ludovic's Uncle Jacques marries Marthe's feisty mother. At the wedding reception, Pascal and Karine head off to have a sexual dalliance. Both Ludovic and Marthe know what Pascal and Karine did, Pascal later admitting as much to Marthe. Although Ludovic and Marthe's friendship starts off solely about their respective cheating spouses, it becomes something more. After thinking about the situation over time, Ludovic and Marthe decide to take their relationship into the sexual realm. As time goes on, Ludovic and Marthe become more and more open about their affair, not only to Pascal and Karine, but to their entire combined extended family. Ludovic, Marthe, Pascal and Karine have to decide what to do about what is happening between Ludovic and Marthe, especially as they are now all family who see each other often at family functions.