A global-scale nuclear war has transformed most of the Earth into a barren ocean-less wasteland, resulting in the downfall of modern civilization and a return to a lawless age of barbarism. The survivors of mankind begin to fight each other over the limited supply of uncontaminated food and water still left in the world. The strong ones begin to band together in gangs and armies, fighting each other over territory, while oppressing the weak.
A man named Raoh appears, seeking to establish order in the post-apocalyptic world through his mastery of the assassination art of Hokuto Shinken. With the help of his childhood friends Reina and Souga, Raoh takes on the mantle of the “King of Fist”, as he gradually extends his reign, recruiting new allies in the process, while fighting against rival warlords who seek to challenge his authority.