Undercover High School

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.

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  Seo Kang-joon

  Jeong Hae-sung
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  Jin Ki-joo

  Oh Su-ah
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  Kim Shin-rock

  Seo Myung-ju
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  Kim Min-ju

  Lee Ye-na
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  Yoon Ga-i

  Park Mi-jung
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  Kim Young-ah

  Im Chung-ha
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