Undercover is an upcoming South Korean drama based on the 2016 BBC television series of the same name. Ji Jin Hee and Kim Hyun Joo are set to star in the series, which serves as a reunion project after working together in SBS' I Have A Lover.

In Undercover, Ji Jin Hee will be playing the role of the National Intelligence Service (NIS) agent, Han Jung Hyun. He chose to let go of everything he has and decided to hide his real identity after falling in love with his wife. He will do whatever he can to protect his family from the powerful forces.

Kim Hyun Joo plays the human rights lawyer and the wife of Han Jung Hyun, Choi Yeon Soo. She's nominated to be the head of the Corruption Investigation Office for High-Ranking Officials (CIO). It looks like the couple hides some secrets from each other, which could threaten their marriage.

In the latest teaser of Undercover, Han Jung Hyun and Choi Yeon Soo's relationship will be further tested. The footage begins with the latter preparing for her upcoming nomination. Being a human rights lawyer, she dedicated her life to seeking justice and truth.

The public fully trusts Choi Yeon Soo because of her talent and values. However, a lot of people are eager to bring her down and will do everything to stop her from climbing to the top. As seen in the teaser, the tension is heating up in the hall during her nomination but she seems unbothered by it.

Then, the clip of Undercover shifted to a flashback scene featuring the younger versions of Han Jung Hyun and Choi Yeon Soo -- Yeon Woo Jin and Han Sun Hwa, respectively. The two met during their college years and their love story blossoms.

Han Jung Hyun fell in love with Choi Yeon Soo after seeing her determined to fight for what is right as she and other students swept in a demonstration against the authorities. The two got married eventually but their relationship is threatened a few years later.

In the present, Do Young Geol (Jung Man Sik) tasked Han Jung Hyun to stop Choi Yeon Soo from becoming the head of the CIO. In the teaser, he responded angrily that he would never block his wife from achieving what she deserves.

Undercover is set to premiere on Friday, April 23, at 11 PM KST on JTBC. The series is directed by Song Hyeon-wook.