Yong-gu is a mentally challenged man with an 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 on their own. But one day, when the police commissioner’s young daughter dies in a accident, Yong-gu who happens to find her is falsely accused and gets imprisoned and assigned to Cell No.7. One day, he saves his fellow cellmate from an attack by his rival. In return for saving his life, Yong-gu is granted a wish to see his daughter again. The inmates put their heads together to carry out a daring operation and succeed in sneaking Ye-sung into Cell No.7.
서울예술대학교 졸업. 이명세 감독과 박종원 감독의 조감독으로 경력을 쌓았고, MBC에서 PD생활을 거쳐 〈그놈은 멋있었다〉로 영화 감독에 데뷔. <각설탕>, <챔프> 등을 연출하였으며, 2012년 <7번방의 선물>로 1천만 관객에 돌파하며 흥행 감독으로 거듭나고있다.