Psychologist An Ran specializes in criminal psychological profiling and assists the police in detecting serial murders. One day, a well-planned kidnapping case involved her in a deadly game with a highly intelligent criminal who called himself a "shepherd" and sneaked into her consulting room disguised as a victim. In every round of psychological duel, if she lost a point, an innocent person would die. As she gradually uncovered the true face of the Shepherd, she discovered that behind this game lay the truth about the bombing that destroyed her life three years ago.
