悉心照顾老公和儿子的全职妈妈星野友美(永作博美 饰)、在电影公司供职的职场女强人早川薰(石田百合子 饰)以及家境平庸心宽体胖的三上春子(佐藤仁美 饰),是现年41岁的老同学。学生时代她们形影不离,彼此心中留下了快乐、悲伤的回忆。借着同学会的机缘,好朋友们再次见面,友美却从闲谈间察觉丈夫洋介(藤木直人 饰)似乎和薰抱持着不正常的关系。在一次争执引发的意外后,两人惊讶地发现她们居然互换了身体。万般无奈之下,她们只能各自进入对方的生活,品味着从未有过的生活方式和苦辣酸甜。与此同时,春子的丈夫则和名叫远山冬子(谷村美月 饰)的女性继续保持联系,看似大大咧咧的春子,也隐隐察觉到丈夫的秘密。三个女性,共同经历着人生的变动…… 本片根据冈田惠和的原作改编。Tomomi and Kaoru were best friends in high school, but the differences in their lifestyles have created a distance between them. Tomomi has built a happy family that everyone envies while Kaoru lives for her career as a movie producer. The two friends meet again at the present age of 41 at a class reunion and return to their former closeness. However, things get complicated when Tomomi finds out that her husband and Kaoru are having an affair. Then the two women awake to find their bodies swapped.