Useless Tsuna and Home Tutor Reborn
An infant hitman named Reborn, leaves Italy, where he is off to visit Japan. Meanwhile, in Namimori, Japan, after losing another basketball game and being forced to clean alone, Tsunayoshi Sawada decides to leave school early only to find that his mother hired an infant as his Home Tutor, named Reborn. However, Reborn announces that his intentions is to make Tsuna a good Mafia Boss for the Vongola Famiglia. The next day, Tsuna and Reborn are walking to school and bumps into Tsuna's crush, Kyoko Sasagawa. Reborn notices Tsuna's affection for her and shoots him with a Dying Will Bullet that gives him the strength to tell Kyoko how he feels. However, he ends up making her run away and is forced into a match with the school's Kendo Club Captain, Mochida. Tsuna is able to defeat Mochida with the help of Reborn making him think that Reborn isn't a bad person until he accidentally steps on one of his grenades.
Family Members Acquired
As Tsuna tries to continue his normal life, he meets up Smokin' Bomb Hayato who tries to kill him in order to gain the position of the Tenth Boss. However, with Reborn's help, Tsuna is able to stop him and also save his life from his backfiring Triple Bombs technique causing Hayato to follow him and aim to be his right hand man. One day, with Hayato away to stock up on dynamite, Tsuna plays a game of baseball with the baseball team's regular, Takeshi Yamamoto, but ends up making his team lose and forced to clean the field alone until Takeshi arrives and helps him. Following Tsuna's advice, Takeshi stays behind to practice but accidentally break his arm causing him to attempt to suicide the next day. With Reborn's help, Tsuna is able to save Takeshi from death and gain a new friend. However, Reborn thinks of it differently and thinks that Tsuna has acquired another family member.
Friends or Enemies?
With Reborn at his side, Tsuna can't help but meet more strange people including a 5-year-old crybaby assassin from the Bovino Famiglia, named Lambo, Hayato's older sister who initially tries to kill Tsuna with her poison cooking, Bianchi, a neighborhood girl who attempted to take Reborn away but ends up loving Tsuna when he saves her from drowning, Haru Miura, Kyoko's older brother that constantly tries to get Tsuna to join the boxing club, Ryohei Sasagawa, a perverted doctor/assassin that saves Tsuna from dying from the incurable disease, Skullitis, Doctor Shamal, the head of the school's discipline committee who beats up Tsuna, Hayato and Takeshi, Kyoya Hibari, a professional of being assassinated from the Vongola Family, Moretti, another infant assassin from China who doesn't speak Japanese, I-Pin, Reborn's former student, Dino, and a boy that is able to rank anything, Fuuta.
The Tomaso Famiglia
During Tsuna's Second Year in school, he meets the boss of a rival family the Tomaso Famiglia, Longchamp Naito whose family owns the Desolation Bullet that he uses to get people's sympathy. Reborn forces Tsuna and his family to infiltrate Longchamp's house in order to eliminate the other family but the plan ends up backfiring when Longchamp and his subordinates decide to stay at Tsuna's house while they rebuild the house. Longchamp later gets Tsuna to go bowling with him along with three girls that he thinks are cute.
Peaceful Vacation Ruined: War at Mafia Land
Tsuna's mother, Nana, won two tickets for a vacation and takes Tsuna with her on the cruise ship. However, Lambo, Bianchi, Reborn, I-pin, Hayato and Longchamp follow them and the group arrives at Mafia Land. While everyone else is enjoying their vacation, Reborn forced Tsuna to go to the island's front desk and announce that they've arrived but ends up in the training ground behind Mafia Land when he failed the test to bribe a government official. As Tsuna is trained by Reborn's rival, Colonello, the Carcassa Famiglia arrives and starts an all out war with the families at Mafia Land. With Hayato's help, Tsuna ends up as the leader of the families' alliance and is forced to fight the Carcassa Famiglia. However, Reborn and Colonello easily stops the war and Tsuna's group returns home before Tsuna and Hayato are able to enjoy their vacation.
The Weapon Tuner and The Assassins
One day, a weapon tuner from the Vongola Famiglia named Giannini arrives, and tries to modify the group's weapons. However, he ends up making Reborn's guns useless, Hayato's dynamites as party favors, and Lambo's Ten Year Bazooka to malfunction, making Hayato shrink into a toddler. However, Hayato is able to see some assassins that seems to be invisible to Tsuna, Kyoko and Takeshi. But with Takeshi's help, Hayato is able to defeat the assassins and save Tsuna's life.
*Note: Bold = Won; Italicized = Undetermined
Manga and Anime Differences
- In the manga, this entire arc took place before the Kokuyo Arc. However, in the anime, it was split in into 3 parts: the starting of the anime, after Kokuyo Arc and in-between Varia Arc and Future Arc.
- The introduction of Takeshi Yamamoto differs between the manga and the anime. In the manga, he breaks his arm during practice after he helps Tsuna in cleaning the baseball field and attempted suicide. In the anime, he is one of the players on the volleyball team that invited Tsuna to play for them.
- Naito Longchamp and his subordinates did not make an appearance in the anime due to the Tomaso Famiglia's unpopularity.