In the year 199X, the world was covered by nuclear flames... The road to challenge Ken-oh, the Conqueror of Century's End, will be a long one. Standing before Kenshiro's path are Heart, the homicidal maniac; Shin, the man of Nanto Sei Ken; Jagi, Kenshiro's evil stepbrother; and Souther, the strongest warrior within Nanto Sei Ken. To defeat the Ken-oh, Raoh, Kenshiro attain the secret principles of Hokuto Shin Ken.