Keiichi Yoshinaga, who works for a major construction company receives a sudden phone call from his ex-wife, Junko Aoba. She tells Keiichi that their second son, Tsubasa, who lives apart, has been arrested for murdering his classmate. Keiichi immediately meets Tsubasa, but for some reason he keeps silence. Since Tsubasa shows no signs of reflecting upon his conduct, he is possibly going to an open trial. To overcome this situation, Keiichi consults a lawyer Kyoko Kanzaki who has a child of the same age.