Hyeon-jin Lee

Due to inadequate use of anesthetics, a young boy experiences "intra-operative awareness" during his own heart surgery, hearing every sound and movement of the procedure. The little boy is severely traumatized from this horrific accident. As a result, he ends up brutally murdering a young girl soon after the incident... (imdb)

The film is based on a true yet unsolved murder case from the early 1990s that is known among Koreans as the "disappearance of the frog children." In 1991, five elementary school students told their parents that they were going to hang out on a nearby mountain to catch frogs. They never came back. (imdb)