Lee Yong-gu is a fictional character from the South Korean film Miracle in Cell No. 7, released in 2013. He is portrayed as a mentally challenged man who is wrongfully imprisoned for a crime he did not commit. The film highlights his deep bond with his young daughter, showcasing themes of love, innocence, and the struggles of those with disabilities. Throughout the movie, Lee Yong-gu faces numerous challenges in prison, but his kindness and resilience shine through. The story emphasizes the importance of family and justice, making it a touching and emotional experience for viewers.