The Celestial Records speak of the existence of the Seraphim, a race of divine beings who give blessings to humanity and are offered prayers by them in return. Those who are anointed with the ability to interact with these spirits are known as Shepherds. Hailed as heroes for their prompt appearances in times of crisis, while also being feared for their power, the Shepherds are imprinted in common folklore along with the Seraphim. Sorey is a young human who has spent his entire life living in harmony alongside the Seraphim in the village of Elysia. Fascinated by the myths of the Celestial Records, he explores some nearby ruins with Mikleo—his childhood Seraphim companion—hoping to enlighten himself about the Seraphims' history with mankind. Unfortunately, they become trapped in the depths of the historical site during their investigation. While searching for an exit, they come across a mysterious girl who desperately seeks the help of a Shepherd to save the world, which is on the brink of being consumed by darkness. Despite Mikleo's warning about making contact with other humans, Sorey decides to help the stranger, which unknowingly leads him closer to the dream of peaceful coexistence between man and Seraphim.

The second season of Tales of Zestiria the Cross.

In 2242, the remnants of humanity are forced to live in scattered bubble-like cities across devastated lands. Hiding from toxic rain and hostile lifeforms known as Enders, they survive thanks to a new source of energy from AO crystals. Those tasked with risking their lives to collect AO crystals are called drifters, piloting versatile bipedal tanks with the support of combat androids named magus. While exploring remote ruins with his exceptionally gifted drifter friend Tokio, prospective drifter Kanata uncovers Noir, a seemingly intact magus in stasis. Although she wakes up by herself, Noir has lost her memories and is of no help in Kanata's work. However, amid an Enders attack, Kanata discovers that Noir possesses remarkable combat abilities. The pair now embarks on a journey to not only shed light on Noir's past but also to uncover the location of Histoire—the mythical city harboring secrets of the world that Kanata has always dreamt of visiting.

Despite returning victorious from a dangerous struggle, Kanata and his friends have, in a sense, lost a key ally, the amnesiac magus Noir. Having partially recovered her memory, Noir reverted back to her former personality: that of Mystere, who acts in a patronizing manner toward her master Kanata. However, Mystere remembers detecting a signal from Histoire, a mystical city, during her former life as an artificially intelligent magus. Meanwhile, Tokio disappears from Rock Town while hunting down the ghosts of his past; however, shocking revelations await the deeper his search goes. As Kanata, his childhood friend Ellie, and the magus diva Ciel set out for Histoire, a hostile organization named Ideal sends assassins after them. If Kanata wants to stand a chance at accomplishing his dream, he must uncover the unpleasant truth about Ideal—and some of his closest allies.