A Different Kind of Man (가슴 달린 남자 / Gaseum dallin namja) (1993)

Frustrated with her lack of oppurtunity at her workplace, Hye-seon Kim (Park Seon-Young) decides to do something about it. Hye-seon decides to masquerade as a man and quickly becomes the star employee. Then after she gets assigned to an all important project she meets co-worker Hyeong-jun (Choi Min-Su). As they work together, feelings start to arise between the two and when things can't become more strange, Hyeong-jun's fiance starts to show interest in Hye-seon.