Angelina 'Lina' Kudou Shields flees to Japan just as the Parasites begin invading again, and a rebellion at the STARS base in New Mexico leaves the unit's second-in-command, Canopus, cornered with nowhere safe to turn. Tatsuya and Miyuki Shiba step in to guide Lina to Miyaki Island, a volcanic island off the coast that the Yotsuba family manages, hoping to keep her out of reach while the fallout threatens to erupt into open magical warfare.