A pair of Humanoid twins were brought along during the Project SEEDS expedition. They were named Vash and Knives and they grew at an alarming rate. Under the guidance of Rem Saverem, Vash and Knives were taught about the need for humans to love and cherish life so that what happened to Earth will never happen again. Vash learned this well but Knives didn't because he was always getting beat up by a member of the crew who hated the twins because they weren't human and were more advanced mentally and physically. Thus, while Vash learned to value all lifeforms, regardless of their being good or bad, Knives on the other hand, empathized more with the weak and the abused. He believed that to survive, the abusive should be killed. Since a member of the crew always picked on him, he realized that the entire human race should be eradicated. So he engineered the destruction of Project SEEDS, forced all the ships to crash on a barren planet and killed all the crew, including Rem Saverem, the woman Vash learned to love.

Knives created a pair of guns for him and Vash, he dubbed them "The Instruments for Conquest". Vash, because he cherished all forms of life, chose not to abandon Knives. but eventually, their different outlooks on life clashed and Vash shoots Knives in self-defense. Knives couldn't believe that his own brother would shoot him, he leaves Vash who opts to stay on a SEEDS ship where some humans chose to live. He studies the technology that Rem taught him, technology that would help a barren planet like the one they crashed in more habitable.

Vash learns of another scientist researching the lost technology. The scientist was based on one of the settlements on the planet known as the town of July. Vash then journeys to July to give the scientist the result of Rem's research. To his surprise, he finds Knives waiting for him at the scientist's office. Vash tries to draw, but Knives was faster. he shoots off Vash's left arm and snaps his fingers. A strange reaction then takes place. The gun biogenetically merges with Vash's arm and takes form of a huge weapon. Beyond his control, Vash could only scream as the weapon explodes and levels the entire town.

Framed with the death of the scientist as well as the destruction of the town and its inhabitans, a bounty of 60 billion double dollar was put on the head of Vash - now known as Vash the Stampede the Humanoid typhoon. As you can imagine, a lot of bounty hunters is now after him. But since he is advanced both mentally and physically, he can get out of any situation without anyone getting killed. He does value all forms of life. so what's the problem you say? Two words: Property damage. Since its open season on Vash, every town he enters gets its share of mass destruction because his adversaries hunt him down guns a blazing.

All that damage is bound to send the insurance idustry down on its knees, so a little insurance company called Bernardy sends two agents to babysit Vash The Stampede and minimize the damage he causes. Not that they can do anything offcourse, but the attempts will keep you laughing. And that is basically where the adventure, laughs and tears begin...