Meiji Gekken: 1874

In the year 1333, the Kamakura shogunate government comes crumbling down. A trusted vassal, Ashikaga Takauji, betrays the shogunate and organizes a rebellion. Houjou Tokiyuki, the rightful heir, escapes the massacre with a Shinto priest named Suwa Yorishige to Kamakura. On the run and fighting to stay alive, Tokiyuki sets in motion his plan to reclaim his birthright.

The year is 1863 and as Japan's long festering wounds of political discord erupt into violent waves of street clashes and murder, the Tokugawa Shogunate sends a new force of masterless samurai called the Roshigumi to the aid of the Aizu forces in Kyoto. However the new "police" are anything but a cohesive force and assassination has already split them into two opposing factions. The stronger is led by the brutal Serizawa Kamo and the lesser by the more honorable but less assertive Isami Kondo. It is into this pack of wolves that Ryunosuke Ibuki is dragged by the rabid Serizawa. Forced to be a virtual slave by blood debt, he hates the samurai and everything they stand for. But as he sees how the other half of the samurai live, he begins to believe that there may still be a chance, for both himself and Japan, if only Kondo will step up and take down the mad dog Serizawa!

It's 1863, the twilight of the shogunate, and Japan is on the cusp of monumental change. The streets of the nation's capital are soaked in blood as political upheaval and rising tensions between masterless, wandering ronin and government samurai set the stage for one of the most turbulent times in Japan's history. Young orphan Nio is no stranger to the harsh realities of the world, and yet he can't help but cling to his burning passion for justice and desire to change the world for the better. One day, he crosses paths with two men who will become central figures of the coming revolution: Hijikata Toshizo and Okita Souji, two of the founding members of a group of hated ronin known as the Miburo—who would later become known as the Shinsengumi. Inspired by the efforts of the so-called "Blues Wolves of Mibu," Nio decides to join the ranks to help carve a path to the world he wishes to see. But with new betrayals and reversals every day, will Nio be able to stay true to his conscience?

It is the beginning of the industrial revolution, and feudal Japan is in turmoil. The ruling Shogun are wielding their abusive powers to instill fear and dominance over their oppressed subjects. Beatings, imprisonment, rape and even murder are the adopted tactics chosen to maintain their reign. The bloodshed must end. A group of Samurai have banded together, and, with the development of new weapons and new technology, they have both the will and the hardware to stand up and fight. Ichimatsu is one of these fighters. By day, he works incognito at a local tavern, in the evenings he frequents the brothels, and by the dark of night, he doles out some big-time, gun-barrel justice. He is here to help. He is Samurai Gun.