# Undercover (2021 TV series)

Undercover (Korean: 언더커버; RR: Eondeokeobeo) is a 2021 South Korean television series directed by Song Hyun-wook and starring Ji Jin-hee, Kim Hyun-joo, Jung Man-sik, and Huh Joon-ho. Based on BBC drama series of the same name, it portrays the story of Han Jeong-hyeon (Ji Jin-hee), an agent at the National Intelligence Service, and a Human Rights lawyer, Choi Yeon-soo (Kim Hyun-joo). It aired on JTBC on Fridays and Saturdays at 23:00 (KST) from April 23 to June 12, 2021. The series is also available on streaming media TVING in South Korea. Kim Hyun-joo and Ji Jin-hee previously starred together in Miss Kim's Million Dollar Quest (2004) and I Have a Lover (2015).
The series ended on June 12, 2021 with viewer ratings of 5.2% nationwide and 6.1% in the metropolitan Seoul area. It is its own best ratings achieved during its run.

## Synopsis

Han Jeong-hyeon (Ji Jin-hee) is an agent of the National Intelligence Service (formerly the Agency for National Security Planning), who has been hiding his identity for the past 30 years as a father and owner of a bicycle repairing shop. Choi Yeon-soo (Kim Hyun-joo), his wife and a Human Rights lawyer, becomes the first Director of the Corruption Investigation Office (CIO). These characters are trying to uncover the truth, pitted against a huge force holding a top position. The series tests their relationship as husband and wife when the secret life of Jeong-hyeon comes to light.

## Cast
### Main

* Ji Jin-hee as Han Jeong-hyeon/Lee Suk-kyu
** Yeon Woo-jin as young Han Jeong-hyeon/Lee Suk-kyu
    Lee Seok-kyu is agent at the National Intelligence Service, formerly the Agency for National Security Planning. He was selected as the new agent of NIS when he was in a police academy. At first he was tasked to spy on Choi Yeon-soo under the pseudonym Han Jung-hyun in order to take down Kim Tae-yeol who was targeted by NIS, eventually both of them were in mutual love and got married. Years later, he lives a peaceful life with his family until one day an NIS agent named Do Yeong-geol comes back to his life and he is enlisted to take down his own wife, Choi Yeon-soo.
* Kim Hyun-joo as Choi Yeon-soo
** Han Sun-hwa as young Choi Yeon-soo
    A human right lawyer for more than 20 years. She passed her bar test at the age of 20. A righteous person, she consistently seeks justice for years to Hwang Jung-ho for 20 years after he was unjustly jailed. She joined a mass protest with Kim Tae-yeol, Kang Choong-mo and others to protest against the corrupted South Korean government who failed in protecting Hwang Jung-ho's innocence. In one of a chaotic protest against the government, she met Lee Suk-kyu, under the pseudonym Han Jung-hyun. Both of them ended in mutual love, without her knowing who Suk-kyu was, therefore getting married with him. Years later, because of her consistency in defending Hwang Jung-ho, she is promoted as the Corruption Investigation Office for High-Ranking Officials by the government. However due to this promotion, her husband is tasked to stop her.
* Jung Man-sik as Do Yeong-geol, Han Jeong-hyeon's former senior at the National Intelligence Service, formerly Agency for National Security Planning
** Park Doo-sik as young Do Yeong-geol
* Huh Joon-ho as Im Hyeong-rak, director at the National Intelligence Service

### Supporting
#### Family of Han Jeong-hyeon and Choi Yeon-soo

* Yoo Seon-ho as Han Seung-goo
    Suk-kyu/Jeong-hyeon and Yeon-soo's autistic older son. He has an obsession with bicycles, therefore he helps his father operate their bicycle repair shop.
* Lee Jae-in as Han Seung-mi
    Suk-kyu/Jeong-hyeon and Yeon-soo younger daughter. A middle school student with maturity and intelligence beyond her age. She resembles her mother in everything
* Park Geun-hyung as Lee Man-ho
    Lee Suk-kyu's father and a war veteran, being proud of his son who serves the country like he did in the past. He believes that Suk-kyu went to the US when actually he has to live under name of Han Jeong-hyeon. His health deteriorates as he waits for his son to come back to him. Since Suk-kyu cannot reveal his identity, he spends time with his father in the hospital, posing as a social worker. Man-ho never realizes that his son is always with him even until his death.

#### National Intelligence Service

* Kwon Hae-hyo as Oh Pil-jae
* Joo Suk-tae as Park Won-jong
* Han Go-eun as Kim Do-hee/Ko Yoon-joo, an undercover agent
** Park Gyeong-ree as young Ko Yoon-joo
* Choi Dae-chul as Chu Dong-woo
* Nam Sung-jin as Jo Dong-pal/Cha Min-ho

#### People around Choi Yeon-soo

* Lee Han-wi as Bae Goo-taek
* Bae Yoon-kyung as Song Mi-seon
* Kim Soo-jin as Min Sang-ah, Choi Yeon-soo's best friend in college, and a political reporter for a major media house
** Han Bo-bae as young Min Sang-ah
* Choi Kwang-il as Hwang Jung-ho
** Im Ji-kyu as young Hwang Jung-ho
    30 years ago, he was wrongly accused of a murder case and was sentenced to death. Therefore, while he was incarcerated on death row, Choi Yeon-soo is determined to seek justice for him as his lawyer. However his case hasn't got any shed of light for 30 years, even after his health severely deteriorated.
* Kim Hye-jin as Cha Min-ho's wife

### Others

* Lee Seung-joon as Kang Choong-mo, Choi Yeon-soo's good friend in college, now a high ranking government official working at the Blue House
** Hong Jin-gi as young Kang Choong-mo
* Kang Young-seok as Jung Cheol-hoon, a passionate detective
* Park Jin-woo as Detective Gu
* Son Jong-hak as Yoo Sang-dong
* Song Young-gyu as Kwak Moon-heum, Chief Prosecutor
* Cha Soon-bae as Song Moon-bae, Chief Editor at Daehan Jeil Daily

### Special appearances

* Kim Young-dae as Kim Tae-yeol
    Kim Tae-yeol is a president of Hankuk University Student Council and leader of the mass protest against the government in 1991. Eventually he was accused as a communist and being targeted, then murdered by NIS.
* Jang Eui-don as police university instructor (ep. 1)
* Lim Jung-ok as Nurse Kim (ep. 1-2)
* Kim Dong-ho as Cheon Woo-jin, Im Hyeong-rak's subordinate (ep. 2 & 8)
* Jung In-gi as Kim Myung-jae, Secretary General of the Blue House
* Kim Kyung-min as Mr. Park
* Shim Hyung-tak as Lee Min-yool (ep. 3-4)
    A man who claims himself being intentionally beaten by Han Seung-goo so that Yeon-soo would be hindered to be the new chief of Corruption Investigation Office for High-Ranking Officials. Actually at that time, he abused his girlfriend and being caught by Seung-goo who said that a bigger person might not hit smaller person.
* Park Joo-hyung as drug gang boss (ep. 4)
* Kim Young-woong as subway control room staff (ep. 3)
* Lee Se-na as Kim Da-kyung (ep. 4)
    Ex-girlfriend of Lee Min-yool. Being guilty with Seung-goo's situation, she confessed about what happened between her, Min-yool and Seung-goo to Yeon-soo.
* Seo Joon
* Lim Hyung-guk
* Ahn Se-ho as Kim Kwang-cheol, an assistant to Do Yeong-geol

## Production
### Development

In April 2020, the remake of the British miniseries was announced.

### Casting

In July, JTBC confirmed that with the joining of Yeon Woo-jin and Han Sun-hwa the cast is completed: Ji Jin-hee, Kim Hyun-joo, Han Go-eun, Huh Joon-ho, Jung Man-sik, Kwon Hae-hyo, Park Geun-hyung, Lee Seung-joon, Lee Han-wi, Kim Soo-jin, Choi Dae-chul, Son Jong-hak, Song Young-gyu and Choi Kwang-il. This drama serves as a reunion project for Ji Jin-hee and Kim Hyun-joo after starring together in the 2015 drama I Have a Lover. It also reunites Ji Jin-hee and Huh Joon-ho who both starred in the 2019 drama Designated Survivor: 60 Days. Also reuniting in this series are Jung Man-sik, Choi Dae-chul and Choi Kwang-il who starred in the 2019 drama Vagabond.

## Viewership

| Season | Season | Episode number | Episode number | Episode number | Episode number | Episode number | Episode number | Episode number | Episode number | Episode number | Episode number | Episode number | Episode number | Episode number | Episode number | Episode number | Episode number | Average |
| Season | Season | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | Average |
| | 1 | 763 | 816 | 583 | 736 | 627 | 903 | 628 | 862 | 773 | 988 | 793 | 818 | 847 | 916 | 769 | 1163 | 812 |