会面之日，弘子得知，恭子只希望她假扮昌和的新娘十天，以代替因车祸骨折的真正新娘。看在巨额报酬的份上，弘子欣然同意，留在关根家位于山中的别墅内进行各种礼仪的训练。但随着事态的发展，她意识到关根家的背后似乎隐藏着更为黑暗的秘密…… 根据赤川次郎同名小说改编。
21岁的透（冈田准一饰）爱上了母亲的朋友、年长他二十岁的已婚妇女诗史（黑木瞳饰），他们一见钟情并开始了地下恋情。透的好朋友耕二（松本润饰）也与家庭主妇喜美子（寺岛忍饰）有不伦关系，但情感十分复杂难解，他同时还有一位女友。
A chance encounter. Between the waves and the cliffs. At night. A week later, he got married. For many years, she no longer believed in happiness. They met. They play. They speak. They want each other. As a gift - unconditional. It's like a dance - on the edge of the void. One night. One night only. Their only night.
