Amber Joseph Liu transferred to a prestigious school in Korea, the SM Academy. Since he loves solving puzzles and mysteries, he joined the investigation club. This club is currently solving the mysterious disappearance of Krystal Jung, three hundred years ago. Other students in their school claimed that they see Krystal Jung's ghost roaming around their school. Amber didn't believe in ghost, but what if one of his club member will claim that he can see her and he is part of their club?