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.