Baki Hanma fights a gang of 100 thugs; afterward, he is walked home by Detective Kido and his partner, who watched the fight. Baki then trains and thinks about what he should do to get stronger. Meanwhile, Kuriyagawa, the man who hired the thugs to fight Baki in order to test his strength, pays the gang's leader. Also, Baki watches a sparring match between Yuri Chakovsky, the international welterweight boxing champion, and Dinoy, Thailand's Muay Thai champion.
Baki spars with Yuri. Meanwhile, Kuriyagawa meets with Kaoru Hanayama, a gangster and renowned brawler, to set up a fight with Baki.
Baki meets his friend Reiichi Ando in the woods and stays with him. While there, Baki adopts some of Ando's training techniques, and he camps alone on Yasha Rock, hoping to fight with the Yasha Ape.
Baki Hanma fights a rematch with the Yasha Ape. After very hard fight, Baki eventually defeat the giant monster. Later he and Yasha Ape becomes a friends and Yasha Ape gives Baki his fang.
After returning home, Baki learns that Yuri will be fighting for the heavyweight title, so he visits Yuri at his gym. Meanwhile, Kuriyagawa tells Hanayama that he can't fight Baki until Baki has fought Yuri, but Hanayama has other plans. Before Yuri's title fight, he is attacked by Hanayama who defeats him and destroys his hand.
After being knocked down by Baki, Hanayama flies into a rage in his office. Afterward, he visits his sick mother in the hospital. Also, Baki visits Yuri and his sister, Nina in the hospital before his rematch with Hanayama.
Baki and Hanayama continue to fight, and Hanayama's tattoo is explained.
Baki's father, Yujiro Hanma, shows up after Baki's fight with Kaoru Hanayama. After the story of how Yujiro met Baki's mother is told, Yujiro and Hanayama fight.
Baki explains to his mother why he fights, visits Hanayama in the hospital, and trains. After a brief encounter with Yujiro, who killed the Yasha Ape, which made Baki angry since Yasha was Baki's friend after their fight, they decide that Baki and Yujiro will fight in one month. Baki then meets Captain Gerry Strydum, who tells him of a mercenary group in Hokkaido, and Baki decides to go there to defeat them.
Captured by the mercenaries as soon as he parachutes in, Baki must free himself and fight his way out against Nomura's jungle warfare team (Copperhead, Kuraishi, and the Chiba twin brothers, Sanada and Chiba). Meanwhile, an old friend warns Strydum of Gaia's fighting ability.
Baki fights Gaia (an alter ego of Nomura).
Yujiro Hanma breaks into the Prime Minister's office to prove a point; Baki Hanma fights the swordsman Kurokawa; Yujiro forces the archer Kanemoto to shoot an arrow at him; Baki visits his mother after she is rejected by Yujiro.
All of Baki's friends show up to watch his fight with Yujiro and to help him warm up; meanwhile, Yujiro fights Gaia. Also, Hanayama opens up to Baki about his mother.
Baki fights his own father, Yujiro.
A recap episode. Detective Kido reflects upon his experiences with Baki Hanma, and Hitoshi Kuriyagawa tells Kido about Baki's relationship with his mother and his fight with Yujiro.
Antonio Igari, a pro wrestler, tells Mitsunari Tokugawa, an old man who runs an underground fighting circuit, about Baki Hanma and his recent global travels. In the narrative, Baki is seen training and fighting, and, while in Brazil, he visits a fighting master named Dickson. Learning of the circuit, Baki returns to Japan to meet with Tokugawa, and he fights Tokugawa's bodyguards to earn a chance to enter the circuit.
Flash forward three years: Baki Hanma is now the champion of the underground arena. Mitsunari Tokugawa meets with Doppo Orochi, a great Shinshinkai karate fighter, and asks him to enter his son in the arena. Doppo finds Kiyosumi Katou, a former student, at his dojo beating up his fighters, and he introduces Katou to the arena. Baki trains for a fight at the boarding house where he is staying, where Kozue Matsumoto, the daughter of the woman who owns the house, has a crush on him.
Baki Hanma fights Kousho Shinogi, a master of Cord-Cut Karate.
Kiyosumi Katou spars with the fighters in Doppo Orochi's dojo; Kozue Matsumoto interferes with some bullies that are bothering Baki Hanma, which causes problems for her later; several fighters petition Mitsunari Tokugawa to be Baki's next opponent; Baki trains with Izou Motobe.
Baki fights Mount Toba, a professional wrestler.
Yujiro Hanma shows up after Baki's fight and knocks him out, and Doppo Orochi challenges Yujiro to a fight. After watching Doppo spar with his students, Baki spars with him. Yujiro starts a fight with a group of boxers at their gym, and he fights with Izou Motobe and Baki's next opponent is revealed.
Dr. Shinogi Kureha reveals to his brother, Kousho Shinogi, the Cord-Cutter, why he is fighting Baki Hanma; Doppo Orochi and Yujiro Hanma fight.
The fight between Doppo Orochi and Yujiro Hanma continues; after Dr. Shinogi Kureha performs a medical miracle, he demonstrates his physical abilities to the crowd; one of Kureha's former patients visits Baki.
Baki fights Dr. Shinogi Kureha.
Mitsunari Tokugawa announces his plans for a world martial arts tournament, and fighters from around the world gather for it. In the first fight of round one in the A-Block, Baki Hanma fights Artemis Regan, a professional wrestler; in the second fight of round one in the A-Block, Vale Tudo master Zulu fights Muay Thai master Dentoranee Jitpika.
In the third A-Block match of round one, heavyweight kickboxing champion Rob Robinson takes on the professional wrestler Anton Igari; in the fourth A-Block match of round one, Motobe Izo fights the grand sumo Kinryuzan; in the first B-Block match of round one, the Sambo master Sergei Taktaroff fights Retsu Kaio, a master of Chinese Kenpo; in the second B-Block match of round one, Kato fights the son of the Yasha Ape.
Baki saves the Yasha Ape's son from Katsumi; in the third B-Block match of round one, Hanayama fights the Japanese Kenpo master Inagi Bunnoshin; in the fourth B-Block match of round one, Roland Gustaf, a catch-as-catch-can wrestler, fights Orochi Katsumi.
Yujiro arrives and enters his protégé Amanai Yu in the tournament; in the first C-Block match of round one, heavyweight boxing world champion Ian McGregor fights Taekwondo master Li Moko; in the second C-Block match of round one, biker gang leader Shiba Chiharu fights judo master Hatanaka Kohei; in the third C-Block match of round one, Shorinji Kenpo master Misaki Kengo fights pro wrestler Mike Queen.
Brazilian Jiu-jitsu master Sergio Silva faces pit-fighter Jack Hammer in the fourth C-Block match of round one; Yujiro tries to fight Hammer, but Baki intervenes; shoot wrestler Yamamoto Minoru faces Amanai Yu in the first D-Block match of round one.
Richard Filth, a bouncer, faces Orochi Doppo in the second D-Block match of round one; Roger Harlon, an amateur wrestler, faces the jujutsu master Shibukawa Goki in the third D-Block match of round one; Shinogi Kureha faces Shinogi Kousho in the fourth D-Block match of round one.
The fourth D-Block match of round one continues as Shinogi Kureha and Shinogi Kousho continue to fight; Baki faces Zulu in the first A-Block match of round two.
In the second A-Block match of round two, Igari faces Kinryuzan; in the first B-Block match of round two, Retsu Kaio faces Mount Toba.
In the second B-Block match of round two, Hanayama faces Orochi Katsumi.
In the first C-Block match of round two, Shiba Chiharu faces Ian McGregor.
Andreanof Garland, the last reserver, is introduced when it is deemed that Shiba is in no condition to fight in the next round; in the second C-Block match of round two, Jack Hammer faces Misaki Kengo.
In the first D-Block match of round two, Doppo faces Amanai Yu; Baki takes Kozue to the site of his mother's death.
Yujiro fights against all of the tournament losers; in the second D-Block match of round two, Shibukawa Goki faces Shinogi Kousho.
Igari begs Baki to let him win, and they fight in the first match of the quarter-finals.
In the second fight of the quarter-finals, Katsumi faces Retsu Kaio; Andreanof Garland fights an anaconda to make things fair, since he hasn't fought in the tournament yet, and then he faces Jack Hammer in the third fight of the quarter-finals.
Andreanof Garland and Jack Hammer continue to fight in the third match of the quarter-finals. Also, Hammer's training history is revealed.
Shibukawa Goki faces Doppo in the fourth match of the quarter-finals.
Baki fights Retsu Kaio in the first match of the semi-finals.
In the second match of the semi-finals, Shibukawa Goki faces Jack Hammer.
Baki and Jack Hammer think about the training and hardships they've endured to reach their current level of ability.
Baki faces Jack Hammer in the final match of the tournament. Also, in flashback Yujiro meets Jack's mother in Vietnam.
Baki and Jack Hammer continue to fight in the final match. In flashback to Vietnam, Yujiro breaks into an American base and terrorizes the soldiers; later, Jack is born.
Baki and Jack Hammer continue to fight in the finals as Jack's body breaks down.