One Tree Hill

Tsunayoshi Sawada, otherwise known as Tsuna, is bad at studying, bad at sports, and clumsy at everything he does. But one day, a strange tutor appears before him.

An unexpected transfer student, Hayato Gokudera, arrives in Tsuna's class, and for some reason, Gokudera hates Tsuna right from the beginning. Meanwhile, Reborn forces Tsuna to participate in a volleyball match.

Two strangers arrived in town, searching for Tsuna's house. Meanwhile, Tsuna has become friends with Yamamoto and Gokudera, who is actually a member of the Vongola family.

Haru Miura is a girl who has been secretly watching Reborn ever since she fell in love with him at first sight. She finally makes her move but when she talks with Reborn, she gets the impression from Reborn's words that Tsuna is a bad influence on him.

The Disciplinary Commitee has immense power in Namimoi Middle School, the school that Tsuna attends. School council leader and head Disciplinary Commitee member Kyoya Hibari is the leader of the delinquents, and mercilessly attacks anyone who is weak.

Tsuna is saved from a dog by I-Pin, a small child wearing Chinese clothes. I-Pin uses techniques which can only be described as psychic powers.

Tsuna goes to school in deathperation mode. When he returns to normal, he notices that he was dragging someone as he ran. The boy turns out to be Ryohei Sasagawa.

Tsuna returns home as usual only to find a black car and a bunch of frightening faces waiting for him. Tsuna rushes to his room and opens his door to find a young man quietly sitting in a luxurious chair. The young man's name is Dino.

Tsuna suddenly becomes dizzy and a skull mark appears on his hand. According to Reborn, it is the symptom of an incurable illness known as Skullitis.

Tsuna forgets his lunch at his house and Lambo ends up taking it to him. When Lambo bumps into I-Pin, who is carrying nitroglycerine to her master, a mix-up of packages results in a riot at school!

Coaxed by Reborn, Tsuna blurts out that he's going to tell Kyoko that he loves her.

When Nana tells Gokudera to take care of Tsuna, Gokudera is glad that he's been acknowledged as Tsuna's right-hand man. But when he is unable to protect Tsuna from bees, Gokudera is embarrassed.

The new year has come, but Tsuna’s life is still chaotic as Reborn declares that the customary Vongola New Year Inter-family Battle will be held—with Dino’s Chiavarone Family as their opponents!

Reborn has set up Tsuna on a date with Kyoko. Tsuna is thrilled, but when Tsuna meets Kyoko at the zoo he can’t seem to avoid running into people he knows.

Reborn has plotted yet another competition, as the group is split up into two teams and a snowball fight begins. What started as innocent winter fun has turned into a battle for survival!

Reborn appears to tell Tsuna that the place they're visiting is built exactly like Death Mountain, a secret Vongola training ground that has a survival rate of one in a hundred!

Tsuna is hospitalized because of his injuries from Death Mountain, but his peaceful recovery is continually interrupted by his noisy friends.

It's Valentine's Day and Tsuna is curious to see who Kyoko will give chocolate to.

A boy named Futa, who is being chased by Mafioso, stumbles across Tsuna. Futa is an informant known as Ranking Futa, and it is said that you can control the world if you get hold of his ranking book.

A sudden series of attacks have targeted Namimori Middle School's prefects. Hibari, who went to crush the perpetrator, has yet to come back. According to Ryohei, Kokuyo Middle School students are behind the attacks.

Reborn has discovered that the perpetrators behind the attacks on Namimori Middle School are not ordinary students, but people involved with the mafia.

Yamamoto narrowly wins in battle against Ken Joshima, but Tsuna regrets the fact that he was a burden. Now Bianchi must contend against the girl named M. M., and then the assassin named Birds takes Kyoko and Haru hostage.

Gokudera and the others have been separated from Tsuna, and the main perpetrator of the attacks, Mukuro Rokudo, appears before them.

Tsuna has defeated Mukuro—or has he? It turns out that Mukuro is really Lancia, one of Mukuro’s associates.

It appears as if Hibari has put an end to the battle, but things start to look different when Mukuro shoots himself with a gun.

In response to Tsuna's desire to defeat Mukuro, Reborn creates new items, the Criticism Shot and the X Gloves. Tsuna is powered up as a result.

Spring has arrived and Tsuna has advanced to his second year of middle school.

Kyoko is coming over to Tsuna's house for a visit, and Tsuna cheerfully begins cleaning his room for the event. But after a nap, he finds a man's corpse in his room!

Hana Kurokawa considers the boys in her grade to be monkeys, but amazingly falls in love with Adult Lambo and asks Tsuna to introduce him to her.

Nana wins a magazine prize for a trip to a southern paradise on a luxurious cruise ship. Tsuna is ready to enjoy some rare peace and relaxation…but why are Reborn and the others on the same luxurious cruise ship?

What started as a tropical cruise takes a turn for the strange as the group lands in Mafia Land, a resort island that has an amusement park and a beach.

Tsuna cannot swim, and doesn't want to look bad in front of Kyoko. Fortunately Yamamoto proposes to help him practice at the public pool, but offers overly abstract advice.

Tsuna has taken on a summer job to pay off a debt caused by Lambo, but at his beach workplace he encounters some unsavory high school students who also turn out to be his superiors.