In "199X," civilization was ruined as a result of a worldwide nuclear war and many creatures died out. In spite of these events, mankind survived and entered an age where the strong ruled over the weak, as the few survivors fought over whatever supply of food and uncontaminated water remained in the wasteland of the world.
Kenshiro, the rightful successor to the ancient assassination art of Hokuto Shinken, wanders into a village in search of water when he is caught in a trap and imprisoned by the local defense force. In prison, he befriends a young orphaned girl named Lin who nursed him back to health. When the village is attacked by a biker gang and Lin is taken hostage by their leader, Ken breaks free from his cell and rescues Lin by defeating the leader with his deadly martial art technique. Kenshiro leaves the village and continues his journey, now accompanied by a young thief named Bat. He becomes involved against the KING organization after witnessing the many atrocities they've committed. As he infiltrates the gang's stronghold in the city of Southern Cross, he finds out that the leader of KING is his old nemesis, the Nanto Seiken master Shin, the man who engraved the seven scars on Kenshiro's chest and kidnapped his fiancee Yuria. Kenshiro emerges victorious in his rematch with Shin, only to find out that Yuria is no longer with Shin.