Reborn introduces the OVA as being created by "Dream Entertainment" in his director costume.At the Sawada household in Tsuna's room, Tsuna happily sighs and recalls in a flashback that Kyoko had invited him to go on a trip with her tomorrow. In the present, Tsuna excitedly comments that he's so excited he can't sleep. Reborn then appears and knocks Tsuna out with a hammer. The next day, Tsuna wakes up on a moving bus. He sees that Gokudera, Ryohei, Yamamoto, Lambo, Haru, Kyoko, Futa, and Bianchi are all there. Tsuna desolately mentally states that he should be going only with Kyoko to relax. Giannini then greets Tsuna, announcing that he was the driver. Reborn states that he invited Chrome, but she didn't come; Hibari as well, although Hibari is revealed to be lying on top of the bus. Reborn announces that they would be going all over Japan in two days. Gokudera expresses his excitement about the trip and brings out a backpack-full of snacks; however, Reborn forbids it, stating that meal costs shouldn't exceed 300 yen, and that the snacks exceeding that cost would be taken. Reborn then announces that their first stop was Nagoya; Yamamoto excitedly pipes up that Nagoya was famous for its shachihoko, an animal that has the head of a dragon and the body of a carp. Reborn then announces their first destination is Nagoya Castle, but modifies it into Vongola Castle- Futa adds with his rankings that Nagoya's famous things had fried shrimp ranked in fifth, but Vongola Castle ranked first. The people on the trip that aren't Tsuna's Guardians, with the exception of Lambo, go to the elevator to get to the roof, but Reborn organizes an exercise for Tsuna and his Guardians to climb up to the roof by rope, along with Futa and Giannini joining them as well. During the climb, Tsuna is the slowest, but his Guardians cheer him on. Futa and Giannini go up by Giannini's self-helicopter invention. Reborn then motivates Tsuna by telling him that Kyoko was there, and not to show her his weakness. Tsuna climbs with renewed vigor, but is punched off when he reaches a "miss" on the rope. Tsuna is later transported up to the top, and a photo is taken of them. Reborn announces the next stop as Osaka. They head to the "Tsutenkaku Tower", which means "Heaven-Reaching Tower", but the word "Vongola" is written on the tower. A photo is taken. They then go to dine at a restaurant, where some express their hunger and some express their anticipation for the food. Reborn tells them to eat as much as they want, but they had to pay for their own food. Tsuna worries, stating that he didn't have any money; however, Reborn tells him to get a job and earn money. In the restaurant, however, Haru, Kyoko, Lambo, I-Pin, Reborn, Bianchi, Futa, and Giannini are all eating happily. Lambo orders some more takoyaki, and Gokudera in his waiter's outfit serves Lambo, albeit angrily. Tsuna and Yamamoto are washing the dishes, and Tsuna miserably expresses his desire to eat.
Meanwhile, Ryohei is advertising for an udon and takoyaki shop. Inside appears to be Hibari eating, as well as Ken, Chikusa, and Mukuro eating separately. As Hibari finishes slurping up his bowl, he sees that Mukuro was replaced by Chrome, merely bending down to slurp his bowl after that.
Tsuna, Gokudera, Yamamoto, and Ryohei finally have enough money to buy lunch; however, Reborn announces that lunch time is over and that they were leaving, much to the Tsuna and his Guardians' dismay.
Reborn announces that they are heading to Sapporo City in Hokkaido next. Tsuna expresses his disbelief that they would make it on time, but Reborn smiles and replies that they would fly.
Later, the bus is levitated in the air, with Tsuna in Hyper Dying Will Mode, pulling it. However, the Dying Will Pill's effect wears off and they begin to fall; Giannini activates the flying mode of the bus to make it safely to Hokkaido.When they arrive in Sapporo, they find three snow statues of Reborn, I-Pin, and Lambo. Reborn states that Sapporo was famous for its cold and snowy winters, so he built some snow statues beforehand for the upcoming festival. Futa cheerfully announces that in his rankings of Hokkaido's most famous landmarks or activities, the "Feast of Snow" was leading. Lambo and I-Pin admire their statues, but Gokudera merely shakes his head uninterestedly; however, he sees a gigantic statue of Enzio, who he mistakenly sees to be the creature who was seen in the tenth issue of "Secrets of Mysteries of the World", the "Vongolasaurus". Tsuna tries to convince Gokudera that it was Enzio, but Gokudera remains stubborn. Suddenly, Lambo announces that he was going to pee, and promptly pees on Enzio's statue. The statue subsequently begins to crack, and the actual Enzio bursts out of the snow "statue". Enzio then stomps on Tsuna, Gokudera, Yamamoto, and Ryohei.
Dino, Romario, and the rest of the Cavallone Famiglia members appear, and Reborn reveals that Dino and his men had created the "snow statue" of Enzio just for the "Feast of Snow". A photo is then taken.
Reborn announces that they were heading to Fukuoka, and that they had just gone to Hokkaido and were heading back to Kyushu. While the bus is flying, Tsuna is hung by the neck and pulled on, Tsuna wondering why he was the only one getting "special treatment". Reborn ignores Tsuna and announces that they were going to Fukuoka's Hakata Dontaku Festival, a famous festival that around 2 million people watch each year.
When they arrive, they find an empty building with an inflated arch over them announcing that the building was the Hakata Dontaku Festival's main stage, Tsuna wonders why it is so empty- Reborn replies that they had a low budget this year. A photo is then taken.
At sunset, the group arrives at a "Vongola Hotel", Reborn announcing that they would be stopping here. The boys announce that they would like to stay, with the maids there being Kyoko, Haru, I-Pin, and Bianchi. When Bianchi shows her face, Gokudera collapses. Kyoko cheerfully states to Tsuna that she always wanted to try being a hotel maid. Hearing this, Tsuna falls into a daze, mentally commenting that Kyoko was cute, and that he was glad he was there. Haru then invites them to take a bath.
In the bath, Tsuna, Yamamoto, and Ryohei are all relaxed and Futa and Lambo are happily racing in the water. Gokudera, however, still hasn't recovered from seeing Bianchi's face. Suddenly, they find that Superbia Squalo has entered the bath as well, along with Belphegor and Lussuria. Levi A Than is seen fanning Xanxus, who is relaxing. Tsuna questions why the Varia are here, Squalo responding that they are having their well-deserved rest; Lussuria adds that they are there to create good memories. Belphegor states that Mammon didn't agree to come, however. Squalo aggressively then asks why they were here, Tsuna replying that they are on a "Vongola-style school trip". Squalo angrily announces that they would be fighting them to punish them for coming to the bath, with a battle called "Varia vs. Trash".
Squalo throws a bucket of water at Tsuna, and Tsuna is knocked into the water. Gokudera, Yamamoto, and Ryohei clash with the Varia members with their water buckets as well. Xanxus, irritated, comments that it is hot, and Levi A Than rushes to cool Xanxus off; however, he is hit in the back by water. Levi A Than retaliates with a blast of his own, but finds himself facing Hibari, who angrily states that those who made a ruckus in the bath would be bitten to death, promptly sending Levi A Than flying. Tsuna expresses his great surprise that Hibari was present, and wonders when Hibari came along with them.
Meanwhile, Squalo uses Scontro di Squalo: Bath Version, sending water from the bath flying everywhere. Hibari, however, rotates his tonfas and sends water to clash with Squalo's attack. Futa and Lambo hide nearby, Futa commenting that a relaxing time in the bath turned into something terrible. Lambo climbs to the girls' bath, despite Futa telling Lambo to be a man and stay.
As Lambo is about to cross into the girls' bath, a blast of water hits him and Lambo is sent flying into Gokudera's head. Lambo, crying, takes out his Ten Year Bazooka, but accidentally shoots Gokudera, who is reverted into his baby form with his present year mind.
Suddenly, the bazooka malfunctions and hits Gokudera, Yamamoto, and Ryohei, switching themselves with their future selves. The ten year later forms of the Guardians express their surprise at their location, but Lussuria suddenly attacks Tsuna. Future Gokudera, however, blocks the attack with Sistema C.A.I. and determinedly states to Lussuria that he won't allow him to harm Tsuna. Future Yamamoto comments that Gokudera got feisty, and uses the Shigure Soen Ryu's eighth stance bath version, Shinotsuku Nettou. Future Ryohei charges and uses Maximum Ingram: Hakata Version, hitting Squalo and Belphegor.
However, the Varia are hit by the Ten Year Bazooka and switch places with their future selves. Tsuna, seeing no other option, goes into Hyper Dying Will Mode and uses Zero Point Breakthrough: First Edition to freeze everyone in the bath, himself included.
Tsuna and his Guardians are freed from the ice and head to eat dinner; however, they find the adult Varia members waiting for them, ready to fight, staying in their adult forms because of the Ten Year Bazooka's glitch. Reborn announces that the dinner conflict between the Varia and Tsuna's Guardians would start, where the winners would get to eat the food. Haru, Kyoko, Futa, and Giannini cheer Tsuna's side on.
Squalo wonders where Fran is, but Lussuria answers that he wasn't with them ten years ago, so he wouldn't partake in the event. Belphegor adds that Fran wouldn't participate, anyway. Squalo then announces that he would start, and thrusts his sword towards Gokudera; however, he suddenly lifts it up and a spinning top comes to the edge of the blade; Haru and Kyoko applaud the action. Tsuna realizes that they were going to partake in a talent show.
Gokudera rises and tells Uri to jump through a hula hoop; however, Uri simply jumps up and scratches up Gokudera's face. Reborn announces Gokudera as the winner, much to Squalo's anger, asking why. Reborn answers that the talents should make the audience laugh.
Reborn announces the second round to be Belphegor versus Ryohei. Belphegor carves a swan out of ice, Ryohei tries to combat it by doing 1000 push-ups; Reborn interrupts and announces Belphegor as the winner.
Reborn announces the third round as Yamamoto versus Lussuria. Yamamoto balances his sword on his head and twirls around, stating that he often did so in baseball training, just with a baseball bat. Lussuria scoffs and takes off his sunglasses, disturbing everyone present. Reborn announces Yamamoto as the winner.
Reborn announces the fourth round as Lambo versus Levi A Than. Reborn, as a result, automatically gives the round's victory to Levi A Than, who had already prepared many different things to perform for nothing.
Reborn announces the final match as Xanxus versus Tsuna. Xanxus states to Tsuna that he would win indefinitely, but Tsuna tries to calm him down, stating that it was just a casual competition. Levi A Than, meanwhile, endures with a candle strapped to his forehead. Xanxus angrily gets up and holds his hands as if holding guns; however, Xanxus doesn't have the guns, and Squalo covers him up with a curtain, telling everyone to forget about what happened. Tsuna wonders where they got the curtain.
Reborn announces that Xanxus was disqualified, and that the score was 3:2 in Tsuna's team's favor.
Tsuna and his Guardians express their happiness at finally being able to eat dinner; however, they find that the Vongola Box Weapons had given it all to Hibari.
Later, into the night, Reborn begins telling horror stories, scaring Tsuna. In the night, Tsuna is awake, and Lambo comes to him, needing to pee. Tsuna is frightened, but relaxes, seeing that it was Lambo. Tsuna notices that he needs to use the restroom, and his Guardians and Futa go along with him. As they walk down the hall, they see three lights levitating; scared, they run off. The lights are revealed to be candles held by Kyoko, Haru, and I-Pin, Haru expressing her worry. Kyoko brushes it off, commenting that the atmosphere was breathtaking, to which Haru replies to Kyoko that she was fearless.
Meanwhile in the boys' room, they wonder if the lights they saw were actual souls. Gokudera, however, suddenly goes blue and points out to the others that the lady on the painting in their room, who was there before, was gone, causing everyone in the room to scream. The Varia members and the other people tell them to quiet down. Reborn, however, comes out of a trapdoor and flips the painting around, revealing that the painting was a double-sided one, with the lady on one side and the other side without.
The next day, they leave on the bus to Tokyo Tower. Reborn reveals that the Ninth had asked Reborn to compile an album of photos of landmarks of Japan for him, and that they now would have a complete album. Tsuna expresses his disbelief that Reborn started that "school trip" for the album, and notices that Tokyo Tower looks weird; Gokudera, however, expresses his amazement that the Tokyo Tower had a crown of Reborn on the top, much to Tsuna's shock. Tsuna exasperatedly tells Reborn not to stick his head wherever he goes. The final photos of the album are then taken.