Japan has withdrawn from the U.N, cut ties with all countries in the world and built and impenetrable electromagnetic force to prevent any outsiders from entering their borders. In response to their self-imposed isolation, America send a high-tech commando unit to gather information on their highly advanced robotics research. After one unsuccessful attempt Vexille, leader of the American commando unit, is determined to succeed in their next mission. Once they arrive in Japan Vexille is separated from her unit and realises the enemy forces had anticipated their mission and were lying in wait. Teaming together with resistance fighter Maria, Vexille leads an attack on their artificial, offshore fortress.