Season 1

Thwart the strong and help the weak. A boy who lives up to the motto "a righteous delinquent" transfers to Nekketsu High School. His name is Kunio. On his first day at school, Kunio puts on the legendary "White Uniform," which has been handed down at Nekketsu High School for generations as a symbol of the top delinquents in Japan, and he becomes the target of gang leaders from all over the country.

The "Tenkaichi Bancho-Kai," a tournament to determine the strongest bancho, is held. The winner will be given the official right to obtain the "white uniform" that Kunio wears, and so the most skilled delinquents gather one after another from all over the country. While Kunio and Riki are steadily winning, Misako, an idol of Nekketsu High School, is kidnapped by Taiyo High School.

Reiho Academy is an elite high school. However, behind the scenes, the Nekketsu High School team is repeatedly being attacked, fearing that they have built a team that can rival their own dodgeball club, which boasts of constant victories. To save the day, Kunio joins the Nekketsu High School Dodgeball Club as a temporary member.

Kunio is set to play soccer against Amemiya, a rival from Riki's soccer club days, for a "white uniform" thanks to a ruse by the Hell gang and Sabu, a yakuza gang member. Kunio struggles against Amemiya, who continues to play outrageously, but suddenly Kunio's ability as a soccer player is awakened. Amemiya's dark past comes to light.

Under the orders of Hell, the hot-blooded high school is occupied by Sabu and his friends, who come to take the white uniform by force. Not only that, Sabu hypnotized Kunio's friend Hiroshi and turned him into a human weapon. Kunio finds himself in a tight spot. However, Kunio's former enemies, learning of his predicament, gather one after another at Nekketsu High School.

A letter of fulfillment for the final battle arrives from Hell. Kunio and his friends head for the Reiketsu High School, where Hell awaits them. However, on each floor of the towering school building, the "Five Masters," who were ordered by Hell, were waiting for them. Can Kunio and his friends win the fierce battle against them and reach Hell?

Johnny, an exchange student from the U.S., transfers to Nekketsu High School. Johnny used to be a promising basketball player, but in order to earn money for his younger sister Mary's surgery, he has been working hard at various part-time jobs. For Johnny, Kunio decides to enter a basketball tournament with a prize of 10 million yen.

Riki holds in his hand a legendary student bag filled with steel plates. Carrying this bag meant that Riki was the target of hardcore delinquents while demonstrating to those around him that he was the strongest student. However, Riki has found no reason to shake his iron fist at them since his encounter with Yurina, who rejects senseless violence.

One day, Kunio rescued a student, Kurebayashi, who was not feeling well on the street. Kunio's heart flutters at the sight of her dainty appearance and sexy behavior, but Kurebayashi turns out to be a Red Lion, an assassin sent by the Kanto Lion Union, a gang of delinquents led by the Lion King. It was Misuzu, the female guardian of Taiyo High School, who first sensed Kurebayashi's ruse.

The straight-laced Kunio is always determined and always solves everything with one word: "Nekketsu". Misako, however, is not so sure about her future. With Hakuo's encouragement, Misako decides to enter a newcomer audition organized by a famous music producer Onishima, aiming to become a singer, which has always been her dream.

The shopping district in the town where Kunio and his friends live has long since lost its former liveliness and has become completely deserted. Then, a businessman by the name of Togo proposes to hold a town-wide "sports festival" to revive the shopping arcade. The prize for the winner is a special promotion ticket worth 100 million yen, which can be used only in the shopping arcade.

Riki's unexpected injury and the existence of a contestant who has been in touch with Togo has thrown the event into chaos. The "Athletic Meet," which started with great pomp and circumstance to revive the shopping arcade, has somehow taken a sinister turn. Kunio asks Togo to cancel the event, but Tadokoro, who desperately wants the prize money to save the shopping district, persuades him to continue the competition.

There was a series of disturbing developments around Kunio. Riki, Tadokoro, and Riki's senior, The Blue Emperor, were attacked by someone one after another. It was all the work of Sabu, a member of the Kanto Sanwakai, who was after Kunio's white uniform. Driven by remorse, Kunio vows to avenge Riki and the others, and gradually loses himself in anger.