Lucid Dream () is a 2017 South Korean science fiction mystery-thriller film written and directed by Kim Joon-sung (in his directorial debut). The film was released theatrically in South Korea on February 22, 2017. Netflix acquired the film for distribution in all other countries, premiering it on June 2, 2017. Synopsis Dae-ho is a young investigative journalist and single father who has made a few enemies by exposing several corrupt politicians and businessmen. One day, his son is abducted but no ransom is demanded. Dae-ho is convinced it is an act of revenge by one of his enemies who he exposed. Three years pass and there is no development in the case. Dae-ho then learns of a new form of therapy that allows mental patients to relive important memories through lucid dreams. One of the physicians who administer the therapy is Dae-ho's old friend, So-hyeon. Together, they explore Dae-ho's memories of that fateful day and find a new trail in his lucid dream. Detective Song, who was responsible for the case three years ago, decides to help Dae-ho and So-hyeon uncover new evidence. When they uncover the prime suspect of the abduction, it turns out that he has been in a coma. Dae-ho then tracks down a mysterious teenager who keeps appearing in all his dreams. This teenager has invented a way to enter the dreams of others. Dae-ho enters the dream of the prime suspect and learns the truth. Cast Go Soo as Choi Dae-ho Sol Kyung-gu as Song Bang-seop Park Yoo-chun as This Man / Kwon Yong-hyun Kang Hye-jung as So-hyun Park In-hwan as Kang Sung-pil Chun Ho-jin as Jo Myung-chul Jeon Seok-ho as Choi Kyung-hwan Lee Suk as Yoo Sang-man Lee Si-a as Choi Mi-yeon Kim Kang-hoon as Choi Min-woo Choi Dae-hoon as Detective Kim Park Jin-woo as Owner of Matna Burger Restaurant Jo Sun-mook as Photographer Lee Chang-jik as Has-been gangster Kwon Oh-jin as Has-been gangster Heo Sung-min as Big guy Hwang Sang-kyung as Male reporter Nam Sang-ji as Nurse at Song Soo-jin’s clinic Lee Eun-joo as Female doctor at Song Soo-jin’s clinic Kim Mi-sung as Nun director Lim Hwa-young as Choi Kyung-hwan's wife Noh Hee-soo as Song Soo-jin (Song Bang-seop's daughter) Kim Hye-won as Hyo-jung (Choi Dae-ho's wife) Kim Sun-bin as Ahn Sang-joon Kwon Hae-hyo as Director Park (cameo) Lee Jun-hyeok as Joo Noh-geun (cameo) Production When writing Lucid Dream, Kim Joon-sung was inspired by