Kim You-jung and Jinyoung Star in 1932 Seoul Spy Romance '100 Days of Deception'

tvN's new period drama "100 Days of Deception" brings Kim You-jung and Jinyoung together in 1932 Seoul for a spy romance set over 100 days. The series premieres Oct. 10 at 9:10 p.m. KST.

Set during the Japanese colonial era, "100 Days of Deception" follows a pickpocket who becomes a spy and an elite interpreter working at the Japanese Government-General of Korea. The two meet in the heart of enemy territory, and their relationship unfolds over the course of 100 days.

A recently released highlight video lays out how characters with very different goals begin to cross paths.

Yoo So-ran, played by Kim Hyun-joo, returns to Seoul seeking revenge and starts planning the assassination of Sato Shinichi, the new political affairs chief at the Government-General. Sato Shinichi is played by Jin Seon-kyu. To carry out the plan, Yoo So-ran decides to plant a spy inside the Government-General and approaches Lee Ga-kyung, the best pickpocket in Seoul, played by Kim You-jung.

Lee Ga-kyung had been saving money from her pickpocketing to leave Joseon. When Yoo So-ran offers to send her to the United States, she takes the deal. She then goes undercover as a trainee interpreter at the Government-General. The mission is set to last three months.

But her first day there brings a face she did not expect. Sato Hideo, also known as Kim Tae-woong, is a senior interpreter at the Government-General. He is played by Jinyoung. The two had met once before at Seoul Station, and Sato Hideo already knew that Lee Ga-kyung was the pickpocket who had stolen his wallet.

When Lee Ga-kyung pretends not to recognize him, Sato Hideo says, "Your pickpocketing was very impressive. Mine was terrible." The scene also reveals that Sato Hideo, the adopted son of the political affairs chief, is Korean by birth and was later adopted. Lee Ga-kyung shares a piece of her own past in return, saying, "My mother abandoned me too." Their relationship begins in mutual suspicion but starts to shift as time passes.

The video also reveals the story behind Geum Seo-hee, the false name Lee Ga-kyung uses at the Government-General. "Seo-hee… is my daughter's name," Yoo So-ran says. A flashback follows in which Yoo So-ran holds a child as a building burns, and Sato Shinichi and soldiers open fire on villagers.

In the present, Sato Shinichi says, "This is our chance to tear out the roots of the Guguk-dan," referring to a Korean resistance group. Yoo So-ran replies, "Even if we fail, only I will die." The video hints that the two have been locked in conflict for 13 years.

The later part of the video lays out the ties among Lee Ga-kyung, Sato Hideo, Yoo So-ran, Yoo Phillip, and Sato Shinichi. The central story will follow how Lee Ga-kyung's relationship with Sato Hideo shifts as she carries out her mission inside the Government-General.

"100 Days of Deception" premieres Oct. 10 at 9:10 p.m. KST on tvN.