She's on Duty (Korean: 잠복근무; RR: Jambokgeunmu; lit. "Stakeout" or "Undercover") is a 2005 South Korean film about a police detective (Kim Sun-a) who goes undercover in a high school to befriend the daughter (Nam Sang-mi) of an elusive gangster. Despite being heavily marketed, the film was generally considered a box office disappointment.