Eriko is a wife who lives an ordinary, but happy life. She lives alone with her son Shun, as her husband is working far away. One day, Shun goes missing. Eriko receives a call from the police that they had found a boy's body in a lake. That body turns out to be a different boy, and Shun is ultimately found safe and sound...
One year after the incident, a beautiful, mysterious woman moves next to them. From that day on, Eriko's peaceful days start to crumble...