In the mid-Joseon Dynasty, a king was so cruel that it was hard to even speak of him. People called him the 'Yaksha King' because he was a demon who devoured people. Yi Shin, who ascended to the throne and reigned as the king of Joseon, had a reputation as a cruel king. When there was a shortage of eunuchs to serve him, the court offered high wages and even accepted eunuchs instead of sons. Seong Han applied to be a eunuch to pay for medicine for his seriously ill mother and thus entered the palace. He caught Yi Shin's eye and became his night attendant...