Multiple locations are under attack from unknown attackers. At the United Nations Kurobe Research Institute they deploy their latest mech suits into the battle. On the inside Yukina triggers the "cube" and a lonely samurai appears who protects his "princess" Yukina from the attackers. Before Yukina and the institute can figure out who the samurai warrior is, he deploys the cube and activates " the giant" which is a powerful mobile suit warrior. The giant, with the samurai in control and Yukina as an accidental co-pilot, moves forward across Japan to seek and destroy the demons. (thetvdb.com)