The story set in a universe where South Korea is a constitutional monarchy. The Empress regnant, already in her thirties, is still unmarried and without an heir, which prompts the imperial court to look for a suitable Crown Prince. They encounter Lee Hoo, the son of the empress' uncle, and brings him into the palace where he begins to learn the life of a royal. However, another competitor arrives at the court: Lee Joon, the son of another uncle of the Empress. They compete for the title of Crown Prince via a trial of several tasks to determine the worthy future Emperor of the country.

• Huh Yi-jae
• se7en
• Song Yong-sik
• Myung Se-bin
• Park Shin-hye
• Lee Ki-young