Seasons
Season 1
12 Episodes
Season 1
12 Episodes
Ace NIS agent Jung Hae-seong is demoted after a mission failure. He goes undercover at a high school to locate King Gojong's missing gold, meeting his teacher Oh Soo-ah, who sees him as her lost first love, stirring old heartbreak.
Created by: Im Young-bin, Choi Jeong-in
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Seo Kang-joon
Jeong Hae-sung
Jin Ki-joo
Oh Su-ah
Kim Shin-rock
Seo Myung-ju
Kim Min-ju
Lee Ye-na
Yoon Ga-i
Park Mi-jung
Kim Young-ah
Im Chung-ha
Lee Hyun So
Han Seung-jae
Yun Chae-bin
Yun Chae-rin
Kim Sun-min
Ji Hyeon-jun
2017
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2013
2014
2021
2006
2017
2024
2021
2019
2009
1994