Deep Rooted Tree

Synopsis

Early in his reign, King Sejong accidentally causes the death of his in-laws and their slaves in an attempt to save them from his brutal father, King Taejong. Two young slaves, Ddol-bok and his friend Dam, survive but neither knows the other has. Ddol-bok blames the king and vows to kill him to avenge the deaths of everyone he loved. He spends several years becoming a great warrior. Dam, who has a photographic memory, becomes a court lady called So-yi (Shin Se-kyung), but she feels so guilty about her role in the other slaves' deaths that she is mute.

Ddol-bok returns to the palace under the name of Kang Chae-yoon (Jang Hyuk) in order to kill the king. However, he becomes embroiled in the mystery surrounding the deaths of several Hall of Worthies scholars. The deaths were caused by a secret society called "Hidden Root," which was created long ago by followers of Jeong Do-jeon, with the goal of giving more power to ministers and less to the king. King Taejong killed Jeong Do-jeon and all of his family except his nephew, Jeong Gi-joon, who is now the leader of Hidden Root and lives in disguise not far from King Sejong.

It soon becomes known that the king, with the help of So-yi and the Hall of Worthies scholars, has been working for years on a secret project, which turns out to be the creation of the Korean alphabet. While tracking Hidden Root, Kang Chae-yoon and So-yi each realize who the other is. So-yi begins to speak, and when she shows Chae-yoon the simple alphabet and describes how it will give more power to commoners, he is convinced to work with the king instead of killing him.

However, Jeong Gi-joon believes that the new alphabet is a threat to Confucian order, and decides to stop it at all costs. He murders the king's son, but this only makes Sejong more determined. Jeong is able to stop the king's dissemination efforts, and on the day the alphabet is to be publicly announced, both So-yi and Chae-yoon are fatally wounded by Hidden Root members. However, through their sacrifices, the event is successful, and commoners begin to use Hangul.

Cast

Jang Hyuk as Kang Chae-yoon/Ddol-bok

Yeo Jin-goo as teen Ddol-bok

Chae Sang-woo as child Ddol-bok

A former slave who has become royal guard and detective of King Sejong. As a child, Ddol-bok protected his mentally retarded father from the teasing of other servants of the Queen's family. Later, Ddol-bok 's father was arrested and beaten, finally dying in front of him and his childhood friend So-yi. Though he was actually saved by King Sejong, he doesn't know it, and because he blames Sejong for his father's death, has sworn to avenge him by killing the king. He becomes a soldier under a changed name, and also trains under a martial arts master named Lee Bang-Ji, who showed him the way of the leaping martial arts that shows incredible speed, agility, power and stamina. Chae-yoon later becomes a low-level guard along with his friends, because he wants to keep a low profile from the king. He doesn't know that So-yi is Dam, believing that she is dead.

Han Suk-kyu as King Sejong

Song Joong-ki as teen Yi Do

Kang San as child Yi Do

The creator of Hangul. During his early years as king, Yi Do had a strained relationship with his father and harbored guilt for seeing people's suffering and death (including his wife's family) under his father's tyrannical rule. After the death of his father and his wife Soheon, Yi Do (now called King Sejong) employs Kang Chae-yoon as an investigator (unaware he is the same boy whom he spared years before) and is helped by So-yi in the creation of Hangul. He later finds out that Chae-yoon is the same boy who tried to kill him.

Shin Se-kyung as So-yi/Dam

Kim Hyun-soo as young Dam

Chae-yoon's friend who was saved as a child by Sejong's wife and became a court lady. During her early years as court lady, Yi Do apologized to her for his role in her family's death. She feels so guilty about her role in her fellow slaves' deaths that she cannot speak, but she is useful in the creation of Hangul because of her photographic memory.

Jeon No-min as Jeong Do-kwang, "Sambong" Jeong Do-jeon's brother

Yoon Je-moon as Jeong Gi-joon/Ga Ri-on

Choi Woo-shik as young Jeong Gi-joon/Ga Ri-on

Ahn Suk-hwan as Lee Shin-juk

Lee Jae-yong as Jo Mal-saeng

Kwon Tae-won as Choe Manri

Jeon Seung-hwan as Hwang Hui

Cho Jin-woong as Moo-hyul

Sejong's bodyguard and friend who would sacrifice himself to protect his friend.

Park Hyuk-kwon as Jeong In-ji

Jang Ji-eun as Queen Soheon

Kim Ki-bang as Cho-tak

Shin Seung-hwan as Park Po

Song Ok-sook as Do Dam-daek

Han Sang-jin as Shim Jong-soo

Seo Jun-young as Prince Gwangpyeong

Lee Soo-hyuk as Yoon Pyeong

Baek Seung-hwan as young Pyeong

An assassin who was smitten by So-yi when he took her hostage.

Kim Ki-bum as Pak Paengnyeon

Hyun Woo as Seong Sam-mun

Jo Hee-bong as Han Myung-hoi/Han Ga-nom

Jeon Young-bin as Mak-soo

Woo Hyun as Lee Bang-ji

Yoo Hyun-soo as Lee Soon-ji

Shin So-yul as Mok-ya

Shim So-heon as Deok-geum

Baek Yoon-sik as King Taejong/Yi Bangwon (cameo)

Han In-soo as Sim On (cameo)

Choi Il-hwa as Kim Jongseo

Heo Joon-seok as Kkeut-soo

Ryu Seung-soo as Jang Sung-soo

Baek Seo-bin as Jang Eun-sung

Min Ji-young as Yeon-doo's mother

Lee Se-na as Geun-ji

Choi Jung-woo as Park Eun

Jung Yoo-chan as Heo Dam

Jung Joon-won as child with bone cancer

Kim Sung-hyun as Gae Pa-yi

Though his origins are vague, the drama refers him to be from China. He is a master assassin, and his skills exceed those of Kang Chae-yoon, Moo-hyul and Yoon Pyeong. The only one that is equally matched to him is Lee Bang-ji, whom he kills.

Ratings

Source: AGB Nielsen Korea

International broadcast

It aired in Japan on KNTV from July 24 to September 17, 2012, which was followed by reruns on terrestrial network TV Tokyo.

It aired in Thailand on Channel 7 every Monday to Thursday at 2.10 a.m. starting January 14, 2016.

Trivia

Real-life father and son Baek Yoon-sik and Baek Seo-bin co-starred in the drama.