Devil in the Heart

The film centers on Na Ok-min, who is falsely accused of murder and finds herself in a harrowing situation. In prison, she encounters Suh Pil-sun, who possesses an old booklet and a necklace with a peculiar design. As the plot unfolds, Ok-min's mother is murdered, leading to a chain of events that sees those involved in the crime being killed one by one.

As investigators begin to suspect that Ok-min is the serial killer, they discover a chilling pattern: the murders occur while she sleeps. The film delves into the supernatural, revealing that Ok-min's spirit is exacting revenge on those responsible for her mother's death. Devil in the Heart offers a unique blend of horror and mystery that appeals to fans of the genre, particularly those interested in narratives that explore themes of justice and the supernatural.