Taeyeon, Amber, and Sooyoung are no ordinary sisters. They are Assassins. They have accepted an extremely deadly mission, an it is to kill all of the person who is connected with their parents death. Unexpectedly their uncle told them to disguise as a student in the S.M Town E., where they also meet Tiffany, Jessica, and Krystal. What will happen to them now? -------------------------------------------------------------------------------------------------------------------------------