Miracle in Cell No. 7

Lee Yong-gu is a mentally challenged man with the intelligence of a 6-year-old, which is actually the age of his own daughter Ye-sung who is much smarter than her peers. The two of them lead a happy life while Yong-gu makes a living by working as a parking attendant at a local supermarket. But one day, when the police commissioner's young daughter dies in a strange accident, Yong-gu is the one who happens to find her. He is falsely accused and sentenced to death for abduction, sexual assault, and murder of a minor. Ye-sung is sent to a childcare institution and Yong-gu gets imprisoned and assigned to Cell No. 7, the harshest cell in a maximum security prison.