日理万机的商界女强人玛格列特（苏菲·玛索 Sophie Marceau 饰）精明强干，性感而极富活力。然而正值不惑之年的她，也同样面对着理想与现实、事业与家庭带给她的困惑和彷徨。40岁生日那天，玛格列特收到了一个来自老家的包裹，里面竟然是她七岁时写给未来自己的信。“亲爱的我：今天，我7岁生日，特别写封信给你，提醒你要记住，7岁时说过的承诺和我对将来的梦想……”
接下来的几天，玛格列特同样收到了这样的包裹。儿时那些不愉快的记忆，如潮水般汹涌而至。故事便从这些尘封着童年回忆的信件开始了。

As adults, best friends Julien and Sophie continue the odd game they started as children -- a fearless competition to outdo one another with daring and outrageous stunts. While they often act out to relieve one another's pain, their game might be a way to avoid the fact that they are truly meant for one another.