As the world accelerates toward its own destruction, Kiba and Cheza—with the help of Tsume, Hige, Toboe, and Blue—race to reach true paradise before the entire world is rendered uninhabitable. Now reunited, Cher and Hubb decide to accompany the wolves in hopes of seeing the journey through to its end, while a distraught and confused Quent wanders aimlessly into the wasteland with his mind fixated on revenge. Meanwhile, Lord Darcia the Third has finally put his plot into motion and pursues Cheza, pitting him against the pack. As everything falls apart yet simultaneously falls into place, the wolves struggle to survive in an increasingly dangerous environment. Though the end draws near, paradise seems further away than ever before. [Written by MAL Rewrite]

The OVA will be based on the Narumi Seo character map story event that was featured in the smartphone game in April 2018. Seo, who has a unique memory disorder, will appear alongside other heroes of the Seo Research Laboratory in the OVA.

The story of this fourth installment takes place amidst signs of postwar reconstruction in the winter of 2028. Tensions are rising in New Port City as demonstrations are held concerning the interests of foreign cartels. This leads to a shooting incident involving riot police. It all started with a cyberbrain infection released by the terrorist "Fire Starter." An independent offensive unit led by Motoko Kusanagi entrusts the suppression of the situation to their ghosts and aims for their own justice. Below the surface of the incident, lies the "tin girl" Emma and the "scarecrow man" Burinda Junior. As Kusanagi deals with the incident, she draws near to what those two ghosts were seeking. (Source: ANN)

In the year 2027, a year following the end of the non-nuclear World War IV, a bomb has gone off in Newport City, killing a major arms dealer who may have ties with the mysterious 501 Organization. Public Security official Daisuke Aramaki hires full-body cyber prosthesis user and hacker extraordinaire, Motoko Kusanagi, to investigate.

(Source: Wikipedia)