Cinque Izumi, Nanami Takatsuki, and Rebecca Anderson must once again embark on a journey to the continent of Flonyard and participate in the friendly war games of the three allied nations: Biscotti Republic, Galette, and Pastilage. Cinque is Biscotti’s hero, who also happens to be the cousin of Galette’s hero Nanami. Rebecca is Pastillage’s hero and a dear friend of Cinque. Dog Days'' begins in the human world. Rebecca prepares her things for her journey back to Pastilage from Japan. Meanwhile, Cinque and Nanami set out to travel to Biscotti and Galette, respectively, all the way from England, when suddenly, a freakish streak of bad luck—in the form of lightning, of course—sends them off course. They soon find themselves in the great Dragon Forest, protected by a Dragon Priestess named Sharu. The Dragon Priestess informs them that demons threaten to invade the forest, as well as the whole continent of Flonyard! It looks like a real war is about to begin in Dog Days''. Can these three heroes save the whole continent from these evil beings?

Special episode delivered to customers who pre-order all six Blu-ray and DVD volumes of Dog Days''.

The series takes place four years after the events of Mahou Shoujo Lyrical Nanoha StrikerS, during which, magical girl Nanoha Takamachi rescued and adopted a young girl named Vivio, who is the reincarnation of the Sankt Kaiser, Olivie Segbrecht. After entering her fourth year of elementary school, Vivio is given her own intelligence device, Sacred Heart, and gains the power to transform using her adult Sankt Kaiser mode. She soon comes across a girl named Einhart Stratos who, similar to Vivio, is the descendant of another Sankt Kaiser ruler, Claus G.S. Ingvalt. As Einhart becomes determined to prove her fighting style is the strongest, Vivio befriends her and together with her friends, enters a martial arts tournament where they fight against various magical opponents and learn more about their past lives. (Source: Wikipedia)

Recap of the Mahou Shoujo Lyrical Nanoha ViVid TV anime.