Season 1

Chokkaku is the eldest son of Ishigaki Kotayū, a low-ranking samurai of the Chōshū domain. His father gave him his name with a charge: to live straight, with nothing to be ashamed of as a samurai — turning even a corner at a right angle. True to that name, the boy has grown up perfectly straight. This spring he passes the entrance examination for the domain's most prestigious academy, Hagi Meirinkan, and begins his days in pursuit of bushido. But at the entrance ceremony itself, Chokkaku already finds himself in trouble with the upperclassmen.

Gō Shintarō, beaten by Chokkaku in a sparring match, vows to redeem himself as a samurai and openly challenges him at the school's martial arts tournament. Yet their homeroom teacher, Hosokari-sensei, does not pick Chokkaku as the representative of the Kiku class. Chokkaku settles for cheering from the sidelines — until his classmates' dismal showing wears out his patience, and he draws his wooden sword in defiance of the teachers' shouts. His showdown with Gō is about to begin.

After the tournament, Chokkaku and Gō become fast friends. But word of their daily brawls reaches Chokkaku's father. Angry and grieved, Kotayū declares that if Chokkaku ever draws his wooden sword in a fight again, he will be made to commit seppuku. Meanwhile, Tsukigata and his gang lord it over the academy, using brute force to do as they please. Unable to stand their tyranny, Gō urges Chokkaku to teach them a lesson — but Chokkaku has a promise to keep.

Keeping his promise, Chokkaku endures a savage beating alongside Gō. Disappointed that he will not fight back, his friends drift away. Tsukigata grows ever more arrogant, ordering every student in the Kiku class to strike Chokkaku and punishing a boy who refuses. Chokkaku cannot stand by and watch. Deliberately breaking his promise to his father, he settles the score with Tsukigata and his gang using his signature move, the Chokkaku Slash.

Hearing of the brawl with Tsukigata, Kotayū prepares to commit seppuku — but the castle steward, Tachibana Kaoru, stops him. Tachibana thinks highly of Chokkaku's cheerful, upright spirit. The ban on wooden swords is lifted, and Chokkaku is free again. It is at this moment that Hitomi Rintarō transfers in. Bright and academically gifted, Hitomi quickly becomes the most popular boy in the class. Only Gō, having caught wind of rumors about him, grows wary.

Hitomi Rintarō, the toast of the academy, asks Chokkaku to train him in swordsmanship. Hitomi's form is clumsy — yet Chokkaku senses one flash of sharp killing intent and beats him down, earning the resentment of his classmates. Then one day Tachibana summons Chokkaku to the castle. He tells the boy to become the heart of the academy and orders him to stay and think it over. But tonight is the night Tsukigata has challenged him to a duel.

Chokkaku skips the duel with Tsukigata and spends the night turning Tachibana's words over. All he works out is that some force appears to be at work, shaking Hagi Meirinkan to its foundations. Meanwhile, Tsukigata's gang resumes its bullying, and the Kiku class — with Hitomi at its center — stands against them. Chokkaku returns just as violence is about to erupt, defeats Tsukigata once more, and wins back the students' support. At last Hitomi reveals what he is really after and challenges Chokkaku to a one-on-one match.

"I want you to make Hagi Meirinkan an academy of both letters and martial arts," Tachibana tells Chokkaku. Taking the words to heart, Chokkaku sets up a training ground on campus and puts out a call for members — but only Gō and two unreliable students turn up. Just as he is sinking into despair, an invitation to a martial arts tournament arrives from the newly founded Daimon Academy. Convinced that a strong showing there will double their numbers, Chokkaku and Gō sign up at once.

The tournament finally begins — but it was arranged by Daimon Academy to drag Hagi Meirinkan's name through the mud. In the tense air, Hagi Meirinkan struggles; even Gō, superb with a sword, can barely get past three opponents. With everything on the line, Chokkaku racks up win after win with the Chokkaku Slash and draws roars from the crowd. Last of all stands Daimon Academy's finest fighter — the very center of that school, and a master of the martial arts.

Chokkaku's performance at the Daimon Academy tournament becomes the talk of Hagi Meirinkan. Welcomed back with cheers, he founds a kendo club to root the ideal of letters and martial arts in the school. Recruitment is hard going at first — and the ones who lend a hand are Tsukigata and his gang, Chokkaku's foes since the day he enrolled. Just as the castle steward Tachibana intended, Hagi Meirinkan begins to come together around Chokkaku.

With help from Tsukigata and Gō, the Hagi Meirinkan kendo club is steadily gaining members. Chokkaku's training is a little over the top, but his friends are visibly improving, and he begins to feel that turning the academy into one of both letters and martial arts is within reach. Then one day a transfer student arrives: a boy who has been studying Western learning in Nagasaki. His name is Hōjō Terumasa, grandson of the former castle steward, Hōjō Terumori.

Word of Chokkaku's exploits at the Daimon Academy tournament spreads beyond the school. Hearing of it, the all-female Shigetsu Kendo Club sends him a written challenge. Tsukigata and the others sneer and refuse to take it seriously — yet led by their captain Kigisugi Jun, every one of them is highly skilled. Jun challenges Chokkaku to single combat, and her attacks launched from horseback leave him purely on the defensive. How will the fight end!?

Jun's sharp swordsmanship drives Chokkaku back to the edge of a sheer cliff. Just when all seems lost, he seizes a single instant and turns the fight around. Jun is impressed — and she has also noticed that, throughout the exchange, Chokkaku kept positioning himself so that she would not fall. Watching the two of them, Terumasa loses patience and challenges Chokkaku to single combat…

When Kotayū learns that Chokkaku injured Terumasa in their duel, he works himself into a frenzy over how to apologize. No reprimand comes, however, and the relieved Ishigaki father and son enjoy a bath in the garden. It is then that Jun visits the Ishigaki house. She speaks to Chokkaku of how vital it is that bushido be passed on correctly at Hagi Meirinkan, laments that she was not born a man, and promises him her full support.

Encouraged by Jun, Chokkaku installs at Hagi Meirinkan the same contraptions his father used to toughen him up in the garden at home. His friends are bewildered at first, but Gō and Tsukigata soon learn to dodge the traps' attacks. The training pays off handsomely — except that it gets in the way of studying. As Chokkaku frets, Jun proposes a plan: build a proper dōjō so the students can throw themselves wholeheartedly into martial practice.

Everyone agrees to the dōjō. Jun will pay half the cost, and the kendo club members will make up the rest between them. Then Chokkaku realizes something: unlike the other students at Hagi Meirinkan, the Ishigaki family are low-ranking samurai. They are not well off, and he cannot possibly raise the matter of money with his father. He tries to earn the funds himself with a stall at the festival, but nothing sells. Just as he is at his wit's end, encouragement comes from Katsuragawa-sensei — the teacher who recommended him to Hagi Meirinkan.

Heartened by Katsuragawa-sensei's words, Chokkaku catches wind of a sumo tournament — with a prize of five ryō! To raise money for the dōjō he enters with his father, and his nimble footwork carries him past four opponents. Then the fifth steps up: a mountain of a man who seems to tower out of sight. With Ayano and Jun cheering him on, Chokkaku uses speed to run the giant ragged, but at last the man catches hold of him…

With the dōjō funds finally in sight, Chokkaku can breathe easy — until the castle steward Tachibana comes calling. Holding Terumasa's guitar, Tachibana bows his head and asks Chokkaku to become the boy's friend. Chokkaku accepts readily, visits the Hōjō mansion, and takes Terumasa out into the town. Guided by Jun, they arrive at the newly built dōjō, where Chokkaku throws himself into practice with his friends. In a corner of the hall, Terumasa is left standing all alone.

He was meant to become Terumasa's friend, yet he left him feeling lonely. Chastened, Chokkaku invites Terumasa to his home. The whole family is delighted, heating the bath and preparing a meal, spared no effort in welcoming him. Terumasa keeps up his usual sour remarks, but with Chokkaku's mother he turns honest and open. Chokkaku is satisfied that they have grown close — but that night, gazing up at the moon, Terumasa wears a lonely look.

On Hōjō Terumori's orders, Terumasa's study companions are to be chosen from Hagi Meirinkan. Named are the well-born Yukisa Takuma, the academically brilliant Gō, and Chokkaku. Chokkaku moves into the Hōjō mansion, where for some reason Yukisa treats him with open severity. Chokkaku pays it no mind and struggles to become a good friend to Terumasa — while Terumasa, for his part, tries to make trouble for him, acting spoiled and setting nighttime pranks…

Yukisa is harsh for reasons of his own, but Chokkaku spends his days as Terumasa's study companion alongside his good friend Gō. What Chokkaku wants is to become a true, close friend to the boy. It is an uphill struggle, yet he feels they are slowly drawing closer. Then one night, thieves break into the mansion. In the confusion, Chokkaku is seized by the intruders for reasons he cannot fathom. What fate awaits him!?

The day comes for a long-awaited return to Hagi Meirinkan. Chokkaku and Terumasa, absent for some time, are greeted with cheers by their classmates. Yukisa, abandoned by his fellows, lets his hatred of Chokkaku explode. Threatening him with a rifle, Yukisa locks him in a mountain hut and lays out his ambition. Chokkaku burns with rage at a boy who thinks only of using Terumasa — but he cannot move. Then Terumasa comes running to save him!

The abduction is never made public. Yukisa withdraws as study companion, leaving Gō and Chokkaku. As the year draws to a close, the two are given permission to spend New Year at home. Chokkaku is overjoyed at the thought of seeing his parents again, but Terumasa looks forlorn. To the excited Chokkaku he promises to show him a Western-style New Year. And when the New Year comes, Terumasa welcomes Chokkaku to the Hōjō mansion with piles of gifts and a Western celebration.

Hosokari-sensei, homeroom teacher of Chokkaku's Kiku class, has worn a gloomy face since the New Year began. Takizawa, castle steward of the Tachikawa domain, is coming to observe his class. Hosokari is a devoted teacher, but on the day of the visit his nerves reduce him to a fumbling wreck, and Takizawa declares him unfit to teach. To restore their teacher's honor, Chokkaku and the rest of the Kiku class rise up!

Nearly a year has passed since Chokkaku entered Hagi Meirinkan. He is delighted that promotion will bring him juniors — until he and Terumasa are summoned by Hosokari, who declares that unless both do well on the promotion exams in a few days, they will be held back. In a panic, the two submit to strict tutoring from Gō, who volunteers for the job, and begin studying late into the night. Just then, a boy who has been admitted to Hagi Meirinkan comes to them, complaining that he is being bullied.

The day of the promotion exams arrives — but unable to refuse a junior's plea, Chokkaku and Terumasa skip the exams and go off to settle a fight. Their opponent, Shōtarō, is strong, and with no sleep behind them Chokkaku loses. Having missed the exams, the two are told they will be held back and suspended. During the suspension they slip out of the house — and see Shōtarō supporting a poor household while studying entirely on his own.

"He loves learning that much, and he can't enter Hagi Meirinkan just because he's poor!" Furious, Chokkaku storms the castle despite his suspension and appeals directly to Tachibana. Tachibana seems to be turning something over in his mind, but Chokkaku is nearly expelled for his misconduct. When his father Kotayū hears of it, he is beside himself with rage. He subjects Chokkaku to the harshest Spartan discipline of his life to teach him the spirit of bushido…

Under a domain reform that puts ability first, Chokkaku's father Kotayū is promoted from stable duty to head of the petty stewards. Meritocracy reaches Hagi Meirinkan too, and Hosokari rises from homeroom teacher to vice-principal. Then the new term begins. Terumasa arrives out of the sky on his glider, the "Adobarin," bursting with high spirits, and shows Chokkaku a map of the world. Chokkaku is astonished: the world is so vast, and Japan so small.

Terumasa accidentally overhears his grandfather Terumori saying to Tachibana, "Terumasa is a fool, isn't he…" and begins to agonize over whether he really is stupid. Thinking Chokkaku will tell him the truth, he goes to the Ishigaki house. Chokkaku and his mother welcome the sudden visit warmly, but Terumasa's heart does not lighten. Then his father comes home from work with news: Terumasa has been appointed castle steward!

Several days after Terumasa becomes castle steward, Tachibana, the steward before him, visits the Ishigaki house. He tells Chokkaku to go up to the castle and assist young Lord Terumasa. As Chokkaku brims with eagerness at the chance to work beside his friend, his father recounts the martial deeds of Terumasa's ancestor Hōjō Terutomo and passes on the wisdom of castle service: never defy them — endure. With those words in his heart, Chokkaku strides cheerfully up to the castle.

Unable to forget his grandfather's "Terumasa is a fool…," Terumasa decides that every adult in the castle believes it, and does nothing but outrageous things. Chokkaku grieves at the sight — then learns from Tachibana that Terumori is gravely ill. Tachibana longs to show the old man a splendid Terumasa. Chokkaku tries to fire the boy with purpose, but his efforts come to nothing. At last Terumasa plays the fool in the castle town itself, and the townsfolk laugh him to scorn.

Learning why Terumasa is running wild, Chokkaku goes to Terumori to hear the truth. Terumori welcomes him warmly and tells him of Terumasa's sorrowful childhood. Chokkaku weeps to hear how the boy, raised in a lonely household, never lost his kindness. To help him recover, Chokkaku takes Terumasa to the poorest quarter of the castle town — where the boy meets children who live cheerfully despite having lost both their parents.

Since that day, Terumasa has slipped out of the castle every night to visit the orphans. To help him, Chokkaku keeps knocking the gatekeepers unconscious with his wooden sword. Then one day Chokkaku is surrounded by the castle's officials, who accuse him of dragging Terumasa into the town and ruining his name, and move to confine him. Seething at adults who truly believe Terumasa is a fool, Chokkaku hits on a splendid idea for his friend's sake.

Chokkaku's idea is to build a house for the orphans on vacant land in the castle town. But he is dragged before the court of judgment and sentenced to a hundred lashes for failing to correct Terumasa's conduct. Under the blows, Chokkaku still speaks out for his friend: "Terumasa isn't a fool — he can become a fine castle steward!" As he cries out through the pain, Terumasa steps from behind a folding screen, dressed in formal robes.

Having shielded Chokkaku before the court, Terumasa mends his ways and begins, step by step, to walk the path of a worthy castle steward. But he is still a child, and what occupies his mind above all is the delicious manjū all Hagi is talking about. Chance after chance has slipped by, and somehow he has never managed to taste one. At last Terumasa makes up his mind, slips out of the castle in ninja garb, and heads for the manjū shop…

For his part in helping Terumasa grow into a worthy castle steward, Chokkaku is rewarded by Tachibana with a hot-spring trip for the whole family. Chokkaku is delighted at the chance to be a dutiful son — but Terumasa, knowing nothing of the plan, summons him, and he sets out late. Chokkaku travels to the springs with Terumasa, who insists on coming along, only to find that his parents have somehow not reached the inn. As he frets, he hears talk that the two may have been set upon by bandits.