公元2041年,叛军驾驶世界上最后一台机甲(蝎子形)进攻东部联盟,考古学家在城市下面发现了一台被遗忘的战斗机甲,将它重新组装起来抵抗叛军。。Yujeong, who works as a night shift nurse at a general hospital's cardiology department, is now told that her 12th-grade younger sister, Kijeong, has been arrested by the police as a suspect in an infant abandonment case. Only then does Yujeong start to make desperate efforts to rescue her sister.。