On the verge of Eltria's demise, Kyrie Florian's family departs in a desperate bid to save her ailing father. Unwilling to accept the inevitable, Kyrie embarks on a solitary quest to Earth in search of a cure, defying her sister's wishes. Teaming up with her childhood friend Iris, Kyrie seeks aid from Earth's magical guardians—Nanoha Takamachi, Fate Testarossa, and Hayate Yagami. As she struggles to persuade them to help, Kyrie faces a challenging journey complicated by her sister's unexpected arrival and intervention. Will Kyrie's determination be enough to secure the salvation of her father and their cherished planet?