Tree with Deep Roots is the great saga of king Sejong and the creation of the Korean alphabet. The new script was announced in volume 102 of the Annals of King Sejong, which was published on October 9, 1446, now commemorated as Hangul Day. The publication was officially named ‘The Correct Sounds for the Instruction of the People’, in Korean 훈민정음 or Hunminjeong-eum, but became known as 한글 or Hangul. The new script caused huge controversy as it replaced the Chinese script, and with it threatened the Chinese influence, the existing Confucian order and the Korean socio-political system.

Tree with Deep Roots is a widely awarded television production about the power struggle between king Sejong’s struggle to introduce the script and fight the old order of aristocrats who fear the loss of their power and who are united in a secret society called Hidden Root. The founder of Hidden Root was Jeong Do-jeon, the most powerful medieval Korean aristocrat.