A seemingly harmless reality game show competition turns dangerous as the participants get killed off one by one. The Contestants: Krystal (Jung Soojung) Age: 17 Suzy (Bae Sooji) Age: 17 Kai (Kim Jongin) Age: 18 L.Joe (Lee Byunghyun) Age: 18 IU (Lee Jieun) Age: 19 HyunA (Kim Hyunah) Age: 2