A brief voiceover gives us the setting. In the far, far future where humanity lost the ability to communicate with the city it constructed, that they lived in, and so the city deemed them illegal residents, and began to exterminate humanity. Our story starts generations later.
An aside. Yes. Given the word choice, I'm sure some people would love to make it about the current immigration kerfluffle, but keep in mind this is a Japanese comic from 20-30 years ago, and Japan isn't exactly an immigration capital even now. Also, it's not the first to posit total war between man and machine - Saberhagen's Berzerker stories come to mind, as well as the future of the Terminator movies, of course.
The action starts right away - you see a small team of people scurrying through giant metal caverns and claustrophobic spaces, in search of a new food source for their village - these details being picked up over several minutes from hints dropped in conversation. The team is composed of kids, teens, and if that fact itself didn't show their desperation, it's later reinforced.
They get in trouble...
...and are rescued by a quiet, almost speechless man calling himself "Killy" - who is searching for humans with the net terminal gene.
Already, the similarities with Great Sky River show up - the desperate straights of the dwindling human population that found a sanctuary of sorts, but must still forage in the world of the machines to get by, living like rats in the walls in constant fear of being found, of their sanctuary broken.
And the westerns - a lone stranger shows up, rescuing the hunting party from the "safeguard". Back at the village, he brings with him the chance to survive, to secure a source of food, and perhaps return the city to human control. And so a team of villagers set out.
And so - through numerous twists I won't spoil - the village is brought to the brink of disaster, yet saved, and the lone stranger wanders off on his quest, never to be seen again.
The action sequences are amazing. The 3d-rendered shading style has vastly improved over efforts I'd seen in the past. The characters are memorable, with the competent and wise village leader, "pops" and his dutiful, competent son, are both noteworthy. Despite a few infodumps, they are short, added only as needed, and the personalities are drawn out with economy and clarity.
Well worth watching.