An anime adaptation of Sakugan will premiere October 7th as part of the Fall 2021 anime reason.
Sakugan is a sci-fi adventure story that follows the father-daughter duo of Gaganba and Memenpu. The two of them live with the rest of humanity in an underground labyrinth.
The labyrinth is a dangerous place filled with monstrous creatures, but even so several colonies persist to this day. Gaganba and Memenpu have the unenviable task of collecting ore that’s gathered by specialized machinery. However a chance encounter has them come into possession of a map.
The danger of the labyrinth outside the colonies can’t be overstated, but with a once and a lifetime opportunity before them, the pair set off into the unknown.
— 『サクガン』TVアニメ公式 (@ANIMA_info) August 6, 2021
A summary from MyAnimeList can be found below.
Far in the future, the human beings were pushed into the deep underground world called Labyrinth and they are living shoulder-to-shoulder. The Labyrinth has several colonies with severe settings such as one having an insanely high temperature, while another is full of gold and silver. Among those, in a colony of Pinyin, resides a curious nine-year-old girl named Memempuu and her father Gaganbar. As “workers” aiming for survival, they live with the lowest profession of riding a working robot to dig ore.
One day, Memempuu pestered Gaganbar, a cave examiner who makes maps of the internal part of Labyrinth, to go travel together with her to find her mother. As a “marker,” Gaganba holds the most dangerous yet attractive profession. One step outside the colony is already deemed to be a dangerous area and meeting a huge mysterious creature that loiters the cave, one’s chance of living will be cut down to five percent. Since it is a dangerous racket to explore the unknown world, the map they hold is valuable and can be sold at a high price. However, is the price for their curiosity higher? What could be the cruel truth that is hidden among them? What awaits at the end of the test? In this travel story between a father and a daughter surrounds adventure with family love.