The story takes places during the beginning of the industrial revolution, at a time when feudal Japan was in a state of turmoil. The ruling Shogun are abusing their power to dominate their oppressed subjects using beatings, imprisonment, rape and murder. Determined to end the bloodshed, a group of Samurai have banded together, with the aid of new weapons and new technology, to stand up and fight. Ichimatsu, known as Samurai Gun, is one of these fighters. By day, he works incognito at a local tavern, in the evenings he frequents brothels. However during the night, he fights to deliver justice to his world.

(Source: Wikipedia).