Hiroshi and Mizuho live an ordinary suburban life in Japan with their child. When Mizuho's father dies, her mother comes to live with the couple. Soon after, Hiroshi is accosted by a strange old man who claims to be his long lost father. Hiroshi's mother had told him that his father died to spare the family the shame of the truth that he had abandoned them. Now Hiroshi feels obliged to offer his father a place to stay, but the old man turns the household upside-down with his disreputable ways.