Alien Krowzer plots to conquer Earth, launching attacks using giant creatures, but his schemes are repeatedly thwarted by Jumbrain, a massive robot piloted by Hiroki Tachikawa, captain of Earth Defense Force GAT. Meanwhile, female commander Queen Gorone captures Hiroki and brainwashes GAT members Amami and Kohno to extract information. Hiroki withstands intense interrogation, but Queen Gorone escalates her methods, applying severe sexual pressure in an attempt to break his spirit. Ultimately, Hiroki succumbs, bringing Queen Gorone's plan one step closer to success, leading to a tragic conclusion.