Magical Girl Lyrical Nanoha: The Movie 2nd A's

Several months after the Jewel Seed incident, Nanoha Takamachi prepares to reunite with Fate Testarossa, who has returned from her trial with the Administrative Bureau. Fate, granted clemency for her role in averting the crisis, is now allowed to attend school with Nanoha. But before they can settle into their new routine, a group of dark mages ambushes them. Overwhelmed by the attack, Nanoha and Fate have their mana drained by a sinister grimoire, leaving their devices, Raising Heart and Bardiche, badly damaged. The attackers are the Wolkenritter-Vita, Signum, Shamal, and their familiar Zafila-summoned by the Book of Darkness to fulfill its dark purpose. The book's current owner, Hayate Yagami, remains unaware of its true nature, while the Wolkenritter, forced to gather mana for its completion, carry out their grim task. Stripped of their power and weapons, Nanoha and Fate must quickly regain their strength to stop the Wolkenritter before they complete the Book of Darkness-and unleash its catastrophic magic upon the world.