One after another, Rika's friends are killed while trying to protect her. Takano dissects Rika, but does so without anesthesia, as requested by the latter in an attempt to carve the identity of the culprit behind all the Hinamizawa murders in her mind and prevent the events from this and past worlds from repeating themselves. The villagers are rounded up at the school and gassed to death, while an ecstatic Takano proclaims her ascension to godhood.

A new OVA series to commemorate the series' 10th anniversary.

A new OVA series to commemorate the series' 10th anniversary.

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.