A man wakes up with nothing but a direction and a refusal to accept the world's oldest lie. Back Arrow doesn't stop to question the Wall, doesn't negotiate with it, doesn't respect it, he just keeps moving forward, and everyone around him has to choose whether to follow or get out of the way. The show burns through every obstacle the setting throws at him because it understands that the real conflict isn't the Wall itself, it's the people who've convinced themselves the Wall is permanent. By the end you're not watching a mecha show about breaking barriers, you're watching a man prove that momentum alone can crack a belief system.

A vast Wall surrounds the world of Lingalind, worshipped as a god that shelters and nurtures the land. Once a month it sends down capsules called Rakuho, holding armbands that let their wearers become mechanical beings known as Briheights, and rival nations fight constantly to seize them. One day a Rakuho crashes near Edger, a village on the outskirts, carrying a black-haired man with no memory who calls himself Back Arrow. He insists he came from outside the Wall, a claim that could shake the faith Lingalind is built on. As he tries to cross the Wall to recover his past, he is caught up in one conflict after another in this mecha fantasy adventure.