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The series takes place in the ruins of the Kanto region, after a massive earthquake (which in the OVAs was triggered by a Comet strike) dubbed 'The Great Kanto Hellquake'. Cut off from the rest of the world, The survivors of the disaster are divided between the strong and the weak, and the land becomes a haven for criminals and renegades from around the world. Violence Jack is uncovered among the rubble and demolished granite by the inhabitants of a ruined city, asking him to help the weak people and helping them destroy what, in most cases, are the strong groups commanded by killers and rapists (this is the story line of "Violence Jack: Evil Town"). In the three OVAs, Jack is requested to help different groups, such as the Zone A (later he ends up helping Zone C women) or a small town, as shown in "Hell's Wind". As for the manga, the stories change drastically, the first being the story Violence Jack helping a group of female models in a tropical forest in Kanto by possessing a boy living in said forest in order to fight off a roving tribe of bandits. Although Jack maintains a ruthless facade, he often helps the weak, and expects nothing in return. However, Jack's unpredictable nature means that bystanders get injured or even killed on occasion as a consequence of his vicious fighting style.