(소녀 K)is a August 27, 2011 - September 10, 2011 TV series directed by Kim Jong-Hyun(CGV Episodes 3) South Korea.
Cha Yeon Jin is a high school girl whose outwardly normal existence and reticent character masks her true identity: she is a professional assassin who is seeking vengeance for her mother after watching her killed in front of her eyes. She infiltrates SS1, the secret organization that her mother was connected to, by becoming one of their killers, all the while trying to track down her mother's murderer.
Han Groo, one of the hottest new idol stars, is the lead in this action-packed movie. Her character, Yeo Jin is a notorious trouble maker in school, who hangs out with wrong people. She's the type of person who lives on the edge all the time. One day, Yeo Jin inadvertently gets involved in an illegal arms trade which leads to the tragic murder of her mother. Driven by rage, she joins S-1, an underground crime organization to be trained become an assassin.