Set in the 15th century, The King’s Letters chronicles one of the greatest achievements of King Sejong the Great, the fourth and most famous King of Korea’s Joseon Dynasty. King Sejong, played here by superstar SONG Kang-ho, dreamed of creating a writing system that could be easily used and understood by all the people but many people in his court opposed his desire in order to keep knowledge and power in the hands of the few. Despite these frustrations, the king learns of a monk with special linguistic skills (PARK Hae-il), whom he secretly brings into the palace to help him with his plan.