I just watched this movie and seeing there's no plot outline and no picture on the main IMDb page, I thought it was sad that such a remarkable film was so poorly represented here. It's one of those Japanese animation that has such a great plot that you just get drawn in from the first few minutes, only to be carried away till the end. In this case the end came a bit fast to my taste, the whole movie clocking at 41mn with credits. Well, better be short and great than long and... less than great. So in case you've been wondering about this title, simply stop. Grab it and get ready to follow Ryuhei, with a few online buddies and his unexpected (but resourceful!) young brother Sasuke in the not so abandoned tunnels of the Tokyo metro. You might end up discovering the hidden treasure of the Japanese army, unless you stumble upon Kazilla, the giant monster !! Very well made in all regards, I was surprised went it finished so fast. Near perfect piece of animation.