Chul-soo is a man with an intellectual disability. One day, Chul-soo finds out that a young girl, Saet-byul, who is in hospital is his daughter. And soon, Saet-byul sneaks out…

While investigating a serial murder case, Detective Han Tae Joo gets into a catastrophic incident. When he wakes up, he finds himself transported back to 1988, appointed to work at…