A postman learns that he doesn't have much time left to live due to a terminal illness. A devil then appears in front of him and offers to extend his life if he picks something in the world that will disappear. The man thinks about his relationships with ex-friends, ex-lovers, relatives and colleagues who will be sincerely sad when he dies.
Naho Takamiya (Tao Tsuchiya) is a 2nd year high school student. During the spring, Naho Takamiya receives a letter sent by herself from 10 years in the future. In the letter, she liked transfer student Kakeru Naruse (Kento Yamazaki). Kakeru Naruse carried emotional scars from his mother's suicide and he died one year later. 26-years-old Naho Takamiya thinks about Kakeru Naruse often.
2nd year high school student Naho Takamiya, with the knowledge of what she feels 10 years in the future, takes action to change her future.
Ikuo and Tatsuya are orphans. They live at Mahoroba’s house which is a child and family services home. At their elementary school, they see Teacher Yuko, who took good care of them like a real older sister, killed right in front of them. Ikuo and Tatsuya tell the police what they saw, but the case is covered by a police officer wearing a gold watch.
15 years later, Ikuo (Toma Ikuta) now works as a detective. He is a good person and his arrest rate is the highest at the police station. Meanwhile, using his handsome appearance and cleverness, Tatsuya (Shun Oguri) becomes a high ranking yakuza.
Detective Ikuo and Yakuza Tatsuya have a singular purpose, which is to find the man wearing the gold watch, dig out the truth and reveal the dark side of the police organization.