Boo: Goku is competing in a fighting tournament of the dead. His meets a statement with his new friend and opponent, Paikuhan. On Earth, Gohan is training Gotten and Vegeta is training Trunks. Gohan and Vegeta become shocked at the fact that Gotten and Trunks can reach SSJ at such young ages. There is another Tenkaichi Budoukai on Earth. Gotten and Trunks wanted to attend in the competition, but were banned because they are too young. However, they steal a competitor's costume and wore it. They battle C18 and their disguise is revealed. Piccolo faces someone known as Kaioshin, but freezes upon sensing his opponent's power. Goku is granted a single day of life to fight at the tournament so he is also present. It is Gohan's turn to compete. He has assumed the identity as a masked crime fighter known as the Great Saiyan Man. Gohan powers up and turns SSJ. This blows off his disguise and the audience learns that the Great Saiyan Man is really the nerd Gohan. Spopobitch and Yamu, two competitors with a "M" on their foreheads, fly out to the battle ring and approach Gohan. Then, the two mysterious men take out a lamp and use it to absorb Gohan's energy. Gohan falls unconscious, Spopobitch and Yamu fly's away, and everyone else becomes shocked and wonder what just happened. Kaioshin and his partner approach the Z warriors and revive Gohan. Then, they tell their story. They are really godly beings beyond Kaio and are here to stop the plot of Babidi and Dubler. Babidi is an ugly little being who wants to destroy all life just for the fun of it. Dubler is the Prince of Darkness. Babidi and Dubler are allied at the task of reviving someone called Boo. To do so, a lot of energy is needed. Everyone learns that Spopobitch and Yamu are zombies of Babidi. That is why they absorbed Gohan's energy. Allowing Spopobitch and Yamu to attack Gohan was part of the plan to follow them to Babidi's lair. A new terror breaches over the Earth. The Z warriors decide to help Kaioshin for the sake of their planet, and follow Spopobitch and Yamu to Babidi and Dubler's lair. Babidi and Dabura's minions are killed in the battles to come. Our heroes face Dubler now. Unaware of Dabura's ability to "stone", Krillan and Piccolo are turned into stone. The only remedy to the curse would be Dabura's death. Dubler is eventually killed and Krillan and Piccolo are restored to normal. Learning that becoming Babidi's slave will make him stronger, Vegeta volunteers to become Babidi's slave. A "M" appears on Vegeta's forehead and he turns evil once again. Majin Vegeta looks forward for another battle against Goku and hopes to defeat him once and for all. Vegeta's powers donation to Babidi grants enough energy to revive the fat being known as Boo. Boo is reawakened and Babidi rides around the city on top of him. Cities begin to get terrorize. Majin Vegeta knocks out Goku, but realizes that good triumphs over evil. He regains his sanity and truly becomes good. Majin Vegeta goes off for Boo and fights him. Boo is a lot stronger and has the advantage. In a final effort to defeat Boo, Vegeta self-destructs, hoping that his sacrifice will take Boo down with him. To his dismay, Boo survives. Even in SSJ2, Goku is unable to defeat Boo. Rage increases, and Goku reaches SSJ3 for the first time! Meanwhile, Bulma gathers the dragonballs to revive all the civilians killed by the Majins since the Tenkaichi Budoukai. Boo grows tired of being Babidi's slave and kills him. Then, he purifies himself by fission and splits into two beings. One is pure good, and the other is pure evil. The two Boo's fight and the evil one turns the good Boo into a cookie. The cookie is eaten, and Boo powers up in a body transformation. The fat Boo is now leaner and more muscular. Meanwhile, Gohan heads to Kaioshin planet to receive training. As a sign of respect, he wears the Kaioshin suit. Gohan pulls out the legendary Z Sword and begins to train under DaiKaioshin, the Elder Kaioshin. Gohan is learning how to use his hidden powers without getting angry to go SSJ. Kaioshin reflects at his past. When he was young, he lived in peace with his family at his home planet. Then, an evil sorcerer, Babidi's ancestor, used Boo to terrorize. (At the time, Boo was smaller than how he appears during the current section of the series). Boo killed all of Kaioshin family members. The Kaioshin cursed Boo into his fat form and made him dormant. Kaioshin, his partner, and DaiKaioshin are the only Kaioshin left. Now, years later, Boo has been revived. Gohan completes his training with DaiKaioshin. He chooses a change in clothes to wearing his father's suit and wishes everyone goodbye. Goku wishes his son luck, but envies that he cannot help because he is dead. Kaioshin partner teleports Gohan to Earth. Gohan appears in time to save Gotten, Trunks, and Piccolo. Gohan beats Boo and Boo self-destructs. Thinking they won the battle, Gohan, Gotten, Trunks, and Boo flew off. They saw Satan and Dende on their journey and took them with them. A being flies towards them. It is Boo! Gotten and Trunks fuse again and are in SSJ3. Eagerly wanting to fight again, Gotenks boasts about beating Boo. Taking advantage of the distraction, Boo absorbs SSJ3 Gotenks and undergoes another body change. Now a lot stronger, Boo overwhelms Gohan. Boo throws a fireball at Gohan. Gohan tries to block, but another fireball pushes Boo's fireball away from Gohan. The ally is Tenshinhan. However, Boo prepares another fireball. In the judgment court, King Yamma grants Vegeta life so that he could help save the planet. In Kaioshin planet, the Kaioshin tell Goku about fusion earrings. Kaioshin and his partner demonstrate. Each partner wears one of the earrings and the to permanently fuse. The earrings are given to Goku. He is to give one to Gohan so that he and Gohan could fuse to beat Boo. To bring Goku back to life, DaiKaioshin exchanges his life for Goku. Goku's halo disappears, and DaiKaioshin falls dead. Then, he reawakens with a halo on top of his head. Goku thanks everyone and teleports to help save Earth. Boo is about to throw a huge fireball at Gohan. Goku teleports to the scene and throws a fireball at Boo. Boo is sliced and his legs and lower part of his antennae are cut off. Goku tells Gohan about the fusion earrings and throws one to Gohan. Gohan catches it and prepares to wear it. The cut off part of Boo's antennae engulfs Piccolo and Boo changes into a stronger form again. The cut off lower body of Boo walks and kicks Tenshinhan unconscious. Then, it engulfs Gohan and Boo powers up again. Goku feels despair again. Vegeta appears and aids Goku. Goku tells Vegeta about the fusion earrings and Vegeta finds the earring dropped by Gohan when Gohan got absorbed. Goku and Vegeta are pulled together and become Vegeto! Vegeto beats Boo, but purposely gets absorbed by Boo to save their comrades. The absorption cancelled out the effect of the permanent fusion and Vegeto splits back into Goku and Vegeta. They find and rescue Gotten, Trunks, Gohan and Piccolo by carrying the bodies and escaping through one of Buu's pores. Good Boo is also still in Boo's body. As the characters left Boo's pores, they returned to their original size. Meanwhile, absorbing Vegeto had given Boo enough energy to complete his phase change. He powers up as the escapes from his body takes place, and returns to his original form. "Original" Boo is back. Boo does a giant fireball and blows up the Earth. The newly fused Kaioshin teleports to help Goku teleport Vegeta, Trunks, Gotten, Gohan, Piccolo, Dende and Satan to safety in Kaioshin planet. Boo teleports and follows Goku. Goku and Boo battle. Goku gets beaten and is weak, so Vegeta joins the fight. Vegeta admits that Goku is better than him for the first time and then fights Boo. Buu beats Vegeta and is about to kill him, but Satan pops up and threatens Boo. Boo attacks Satan but Satan dodges the punch. All of a sudden, Boo goes in pain and spits the good fat Boo out. The two Boo's fight and the good Boo gets beat unconscious. Goku and Vegeta continue to face Boo. Vegeta tells Kaioshin to gather the Nameck dragonballs. He does so, and makes the first wish to restore the Earth. The second wish revives all the civilians that Boo killed. The third wish is saved for later. Everyone is back on Earth except Goku, Vegeta and Boo. Goku begins to create a Genki Dama while Vegeta distracts Boo. Our heroes on Earth tell people to raise their hands. Doing so will donate energy to Goku's fireball. However, no one listens. Satan, still famous after the Cell Game, raises his hands. Following the example of their idol, everyone on Earth raises their hands. Goku gets enough energy for his fireball and he fires it. Boo is too strong to get blasted and holds the fireball back. Kaioshin makes the last wish from the dragonballs to restore Goku's energy. Goku's power restores from his weakened state and he uses his revived strength to strengthen his fireball. Boo, unable to repel Goku's Genki Dama, is killed by the fireball. Our heroes have won the battle.