Gintoki's insistence on saving Hajime has caused him to get badly hurt. This match will be decided between Obi Hajime of the School of Beam Saber and Shimura Shinpachi of the School of Tendo Mushin.
Shinpachi saves Gintoki from Kenofi and strikes back at the cyborg. But Kenofi stops it, breaking the sword and wondering why he came when it was too late before retaliating. Kenofi is stabbed by his own beam saber from Gintoki; he is thrown to the side while the badly injured silver-haired man collapses. Shinpachi tells Gintoki that he and the arriving Tae and Kagura were told everything from Yamazaki along with there being no chance to bring back Obi. Gintoki desperately struggles to his feet and under the siblings saddened gazes, tells them that he promised that he will bring back Obi, so wait until he did so; he then cursed himself for his weakened state. Shinpachi tells him it's enough; even if Gintoki succeeds in saving Obi and Earth, it wouldn't be the same if Gintoki dies doing so. Gintoki was never much of an authoritative figure or a role model but as long as he's around to share their pain then they can be happy. He tells the surprised samurai that he will take over; he is no longer Obi's crybaby "little brother" or the Beam Saber School's student, he is instead the Tendou Mushin's heir and the Yorozuya Shinpachi. He asks Kagura to take care of Gintoki while he confronts Kenofi but Gintoki calls out to him, giving the bespectacled boy his bokuto.
Kenofi mocks Shinpachi for thinking that he has a chance when even the stronger Gintoki was no match. Shinpachi remarks that Gintoki was here to save him, not kill him; Kenofi would have already been destroyed if that was the case. He adds that he will bring Obi back, even if he kills Obi and suffer because of it. Tae declares herself the witness to judge their duel, wishing that Obi can see that the Shimura siblings, who have always admired Obi, have become strong enough to stop him. She starts the match and Shinpachi rushes towards Kenofi, calling out Obi's name. Before countering, Kenofi sees Shinpachi attack the same way he did in the past when he and Obi sparred. To everyone's surprise, Obi calls out to him and the two strike. Obi admits how strong the siblings have become before collapsing and Tae declares Shinpachi the winner.
At the same time, the Firestarter group loses contact with Kenofi and the leader angrily berates him for being a useless piece of junk. Kyuubei and Kondou point their swords at the leader and Kondou declares that Obi was not such. He was a samurai that has finally returned home. Before he tells the few Shinsengumi officers with him to arrest them, the floor beneath the cops and Kyuubei open. On Earth, Obi complements Shinpachi's strike but the teen denies it. He reveals that in some of their spars, the instructor had always let Shinpachi win with the usual statement on how much he had grown. Obi responds that he was serious; it was thanks to the siblings and Gintoki that he was able to beat back Kenofi and learn what true strength is. Kagura interjects and tells him not to go and stay with the siblings. He answers that he has some unfinished business in space.
Back on the ship, Kondou holds on to the trap door's ledge while also holding on to Kyuubei. The leader mocks him for underestimating them and remarks that their cyborg was still an unlit bomb with enough power to destroy Earth. He gleefully adds that they will light the fuse themselves. Before Kondou can say anything, he loses his grip thanks to Kyuubei's ingrained reaction against males touching her. The two fall out the ship and safely land in one of the Shinsengumi ships, run by Hijikata. Kondou warns his second in command to stop the ship from firing a laser beam at Obi's location to blow him up. On Earth, Obi rises to his feet, tells the siblings that after he finishes his business he will return and asks Gintoki to take care of them. Gintoki starts to leave, telling Tae and Shinpachi to come. The two tell Obi that they won't cry anymore and the stunned cyborg promises that they will meet each other again before they all leave.
In space, the Shinsengumi bombard the Firestarter ship to little avail as it prepares to fire its cannon. They lock on to Kenofi's location, just to see their creation alive and aiming his own beam cannon at them; the two fire at each other. As Obi disintegrates from the force of his blast, destroying the ship, he thinks back to his words of how laughter is better than tears when it comes to sadness and pain. Unfortunately, both he and the siblings broke their promise. Obi lets out a tear before his own power destroys him and the siblings despite their smiles, start to cry.
A month passes and Kondou and Kyuubei visits the Snack Smile to see Tae daily just to see the owner turn them away. Tae asked for a leave of absence and hasn't returned since, along with Shinpachi. The two are saddened by their failure to save Obi as well as their inability to comfort the siblings in their time of need. Kondou does state that they can only wait until they overcome their sadness and the two will be there smiling when it happens. ... Except the two end up encountering said siblings, back from vacation and sporting a tan. It turns out they had used Obi's life insurance money (meant to be used to revive the dojo) to both go to the Planet Waiiha for vacation and buy large amounts of chocolate covered macadamia nuts. Kondou grows disturbed at how Tae and Shinpachi appear to quickly overcome Obi's death along with deciding to use the treats to revitalize the dojo.
To make matters worse, their first students were a group of homeless that were bribed with the treats. The homeless becomes unruly until they are silenced by Gintoki, who dares them to attack him, the Tendou Mushin Macadamia instructor, to get their nuts. He adds that they should promise to keep smiling even when training and life gets tough. The homeless attack but are pushed back by Kagura and Kondou and Kyuubei decide join in the fray. Shinpachi joins as well, pushed on by his two big brother figures. Tae visits her father's grave, with Obi's grave next to it. She apologizes to Obi for not using the money to revive the dojo but tells him that she, her brother and their friends are doing just fine.
- Sakata Gintoki
- Obi Hajime
- Shimura Shinpachi
- Shimura Tae
- Yagyuu Kyuubei
- Toujou Ayumu (cameo)
- Hasegawa Taizou (cameo)