After suffering through a long and unsuccessful series of fertility treatments, Satoko and her husband Kiyokazu make the decision to adopt a child. Six years after adopting a boy they named Asato, Satoko has quit her job to concentrate fully on her husband and son. The family lives a peaceful existence until the arrival of a stranger.

Toshiko does not have long to live. She wants to make the most of her time while she can and takes a sojourn to where her true hometown for which she has so much nostalgia and admiration. With her husband on her side she remains can-do and keeps her chin up, but can only lament the passing of time and what will happen next to everyone and everything she loves.

On the surface, the Kyobashis appear to be a happy family. Despite a family agreement that they are all open with each other, the entire household knows the opposite is true.