Shidou Itsuka encounters heightened danger because of his ongoing association with Ratatoskr. He has already sealed 10 Spirits, and Isaac Westcott, the leader of Deus Ex Machina Industries, has ultimately resolved to eliminate Shidou and seize the Spirits' powers for his own use. To accomplish this objective, Isaac initiates a full-scale war against Ratatoskr, compelling the organization to deplete its resources in order to guarantee Shidou's survival. Although severely outnumbered and outgunned, a sliver of hope remains in the person of Kurumi Tokisaki, the Spirit of Time. Shidou is required to seal and obtain Kurumi's power so he can journey back in time and face the Spirit of Origin—the catalyst that initiated the entire conflict.