Lee's fourth film, "Secret Sunshine" about a grieving mother who loses her son, was completed in 2007. At the 60th Cannes Film Festival, the film was entered in the competition category with lead actress Jeon Do-yeon, winning the "Prix d'interprétation féminine". It was released to theaters in South Korea in 2007, and was South Korea's submission for the Academy Awards for Best Foreign Language Film in 2008. "Secret Sunshine" won Best Feature Film at Asia Pacific Screen Awards. It won Best Film and Best Director at 2008 Asian Film Awards. It won Best Picture and Best Director at Korean Film Awards, Best Director at Director's Cut Awards, and Special Award at Grand Bell Awards.