The video for the Sakugan anime previews the opening song and the fall premiere

The video previews the opening song of the film "Kо̄kotsu Labyrinth" ("Enchanted Labyrinth") by Masaaki Endoh and also reveals the anime's premiere date in the fall.

The novel's description on the Everystar website reads:

The distant future, long after the Western calendar is no longer in use.

People live shoulder to shoulder, crammed into the "Labyrinth," an underground world deep beneath the surface.

There are many colonies where people live in the underground labyrinth. The place is known for its extremely high temperatures, but also for its deposits of gold, silver, and other riches.

In one of the colonies called Pin-in, a curious nine-year-old girl named Memenpu and her father Gagamba board a two-person work robot and mine for ore. They eke out a living as the lowest of the low "worker" professions.

One day, Memenpu asks her father Gagamba to become a Marker—those who explore and map the interior of the labyrinth as spelunkers—to search for her mother, who has left their home.

If they encounter a "mysterious giant creature" lurking in the caves, the survival rate is less than 5%. Since exploring an unknown world is dangerous work, "maps" in the world of Labyrinth hold high value and fetch high prices on the market.

A Marker is the most dangerous but also the most lucrative job.

Gagamba decides that he can't stop the ever-curious Memenpu from setting out on her own countless times and finally gives in. The two embark on a journey together in the work robot.

But the "price" of curiosity...

The "truth" they eventually uncover...

This is an epic journey of father and daughter with the theme of familial love.