A serial killer is burning away the flesh of his victims with acid, leaving only the bones behind. The police turn to Hyun-min, a former forensic sculptor adept in reconstructing faces by examining and interpreting skulls. With the victim's bones in his house, Hyun-min's daughter begins to experience disturbing visions. As he races against time to find the answers and save his daughter, the deadly truth behind these victims reveals a sinister conspiracy that threatens everyone involved.

Directed by Jang Kil-soo, the film revolves around a boy and his younger sister, who live in poverty yet in a pure and innocent way. A boy named Nan-na lives with his grandmother in a remote village near the ocean. But when he turns four, his life gets tougher as he has a baby sister Ok-yi and all the affection he received starts going toward the baby. The free spirited boy, who behaved as he liked, now has to take care of his sister, and he has no choice but to start hating her and teasing her. But for Ok-yi, Nan-na is the best in the world.

Upon receiving the body of a maid in waiting who was said to have hung herself within the palace walls, dedicated doctor Chun-ryung begins to suspect foul play. Upon launching a personal investigation, however, Chun-ryung quickly discovers a labyrinthine maze of deception constructed by those with limitless power to conceal a valuable secret.