Izo is an assassin in the service of a Tosa lord and Imperial supporter. After killing dozens of the Shogun's men, Izo is captured and crucified. Instead of being extinguished, his rage propels him through the space-time continuum to present-day Tokyo. Here Izo transforms himself into a new, improved killing machine.
In the near future, crime runs rampant in the streets and two major mafia groups are battling for power. In order to eliminate the two mafia groups, the Tokyo Metropolitan Police Department orders an undercover investigation of their headquarters. However, the ones chosen for the mission are four people known as "losers". Will they be able to successfully solve the case?
We follow Ichi during his high school years. Mr. Dai is the best fighter in school... whenever he fights Ichi is there and has a huge smile on his face. Mr. Dai thinks that Ichi is laughing at him but in fact he enjoys watching the violence that goes through the fights. Everyone is bullying, taunting and making fun of Ichi... even little kids from his karate class. Yet Ichi refuses to let go of his anger and fight others. Just when Mr. Dai is about to get Ichi, a new transfer student starts to make his own laws... by beating up everyone and breaking their bones! In a fight with the new student, Mr. Dai ends up on the ground, beaten and broken up from almost everywhere. It seems like this new guy wants to fight Ichi because supposedly he is the only one that could give him some challenge.
Two contract killers cross paths in the middle of the same job and realize they are childhood friends. Together they take a break from killing and visit the small island they once called home. After reflecting on their past lives they decided to team up and use their talents in killing for good... much to the upset of the crime syndicates.
