The fake eunuch is trapped in a palace puzzle, and the orphan of the previous dynasty stirs up the world. The two-faced identity revolves between the eunuch group and the royal family, dancing on the tip of the knife. The turbulent intrigues of the court, the complicated blood feud, and the taboo emotions of the prisoner and princess from mutual testing to life and death alliance are intertwined. While pursuing the truth about the family's destruction, he made a difficult choice between the justice of restoring the country and protecting the people in front of him. When war breaks out across the border, the secrets deep in the palace become the fulcrum that can influence the fate of the dynasty. See how a little person, with the most special identity, can break the chess game in the most dangerous chess game.