黛丝（杰米·李·柯蒂斯 饰）是一个心理医生也是一个单亲母亲，独自抚养女儿安娜（林赛·洛翰 饰）与小儿子。但黛丝跟安娜的关系一直不好，两人都看不惯对方的做法。这天她们再次争吵：为安娜乐队及母亲再婚的事，表示如果换做是对方，事情就会有好的结果。没想到她们读了一位奇怪老婆婆所给的小纸条后，竟然互换了身份。惊恐中她们不得不接受事实，互相配合做好各自的事，这期间经历的事，才让母女认识到各自的生活，理解到各自的感受。但黛丝的婚礼就要进行了，身份还没法换回……
The former star of a short-lived television sitcom, Fabien, drinks too much to remember everything he does and not much surprises him anymore. When his path crosses Yoni’s, he is not surprised to discover, in the wake of this young, tearful, military man, the head of yet another young man, beautiful like a dream, a memory, a reproach.
