It is 1983, and Hinamizawa is under quarantine. A mysterious and deadly virus has been discovered within the small village, and its residents—such as teenager Keiichi Maebara and his friends Mion Sonozaki and Rena Ryuuguu—are left confused and frightened by the situation. As the villagers begin to search for a way to stop the affliction from spreading, some make drastic plans, which leaves Keiichi and his friends looking for a way to escape the village. But when tensions reach an all-time high, some of his group may not make it out unscathed as they fight for their lives against enemies both seen and unseen.

Satake Hirofumi is a prisoner on death row for murdering his fiancée. He's also an "Undeadman" who has survived many desperate situations. For this, he has earned the interest of a research institution called "Human Crazy University," which studies real-life miraculous phenomena and the people who become entangled in them. Now a subject of their research, Satake relates to them his memories of his immortal, yet unhappy, life. Why did he kill his fiancée? Soon enough, the truth sheds light on a much bigger conspiracy...

In the years following a vicious war, the Empire of Zol now controls the land and citizens of rival Aquafa—except for Aquafa's Fire Horse Territory, where wild dogs that once carried the deadly Black Wolf Fever continue to roam free. When a pack of dogs race through a Zol-controled mine, Van, an enslaved former soldier, and a young girl named Yuna are both bitten, but manage to escape as the sole survivors of the attack. Finally free, Van and Yuna seek out a simple, peaceful existence in the countryside. But as the deadly disease once again runs rampant, they find themselves at the crossroads of a struggle much larger than any one nation.

Walküre and Delta Flight used music to save people from the Vár Syndrome, a previously unknown disease that made humans and others go berserk. However, they find themselves facing a new threat…