University student Sugishita Nozomi, Naruse Shinji, Ando Nozomi and Nishizaki Masato end up coming upon the scene of the murder of the Noguchi couple, because of a plan they had devised. Nishizaki is arrested at the scene and is given a 10-year prison term because of his voluntary confession. 10 years later, Takano Shigeru, a former police officer who has misgivings about the verdict of this case, starts to pursue the truth. He is convinced that it all began as a result of an incident caused by Nozomi and Naruse on an island in the Seto Inland Sea in the summer 15 years. "They committed a crime at that time. It was for the sake of each N."

Nozomi Sugishita (Nana Eikura), Shinji Naruse (Masataka Kubota), Nozomi Ando (Kento Kaku) and Masato Nishizaki (Keisuke Koide) make a plan. The plan brings them to the scene of the Noguchi married couple murder case which took place at a super high-rise apartment. The police receives a report and when they get there, they find the four people there.

Based on Masato Nishizaki’s confession and the testimony of others, Masato Nishizaki is arrested for murder. He receives a prison sentence of 10 years.

10 years later, Masato Nishizaki  is about to be released from prison. Former cop, Shigeru Takano (Tomokazu Miura), chases the truth behind Noguchi married couple murder case. He is sure that murder case began during the summer, 15 years earlier, on an island in the Seto Inland Sea.