Every kingdom has its own skeletons in the closet that no one knows about, and if it finds out, a huge scandal will break out. This can even lead to a change of ruler. In the history of Secret Kingdom you will meet a knight girl Grace. She is close to the court and is responsible for the safety of the king. The heroine has to attend the secret negotiations to keep abreast of events. Another secret meeting is coming up today, but they may break down because Grace found out that a secret agent from an enemy state appeared among the courtiers. It is necessary to calculate and open it.