The nightmare descends on Tokyo's prestigious Ginza shopping district without warning as a dimensional gateway opens, unleashing an army of monsters and armored men upon the panicking crowds! One man, though, is slightly better prepared than anyone else: Yoji Itami, a Defense Force reservist and a rabid comic and sci-fi fan who's seen this scenario played out in countless fantasies. That's just enough edge to help rally the police and first responders, turning back the invasion! And for his quick actions, he's rewarded with a promotion, restoration to active duty, and thrown right back into the fire with the vanguard team charged with exploring beyond the portal! But even as he's facing off against elves, beast men, and other fantastic creatures, the worst danger of all is lurking behind him, on the human side of the GATE!