Having another World Martial Arts Tournament funded by X.S. Cash for his son's birthday, Mr. Satan invites everyone on Earth to a competition on a remote island. The Z Fighters all go except Vegeta, and Goku who is still dead and wishes he could compete as they watched the competition with a television. During the elimination rounds, Yamcha falls in the water while he was resting, Tien loses to Future Trunks, and Piccolo forfeits his match against Kuririn out of disgust for the latter's poor attempts at fighting him. Gohan, Future Trunks, Kuririn, and an ordinary fighter reach the final where Mr. Satan's students are dressed as aliens and are to serve as foes for the warriors.
However, Bojack and his four men have changed things in secret. The first is Zangya fighting Kuririn, the second is Kogu and Future Trunks, the third is Gohan against Bujin, the fourth is Bido killing Sumo wrestler Doskoi by strangling him with just one arm. To this, the audience screams in horror, and Tien and Yamcha decide to investigate. Mr. Satan tries whatever he can to avoid getting involved, believing them to be more powerful than Cell.
Kogu manages to get the upper hand on Future Trunks and tried to kill him with his Devilish Blade, but Future Trunks turns into a Super Saiyan and blocks the sword attack, breaking it in the process. Future Trunks then kills Kogu by forcing his fist through his gut. As Future Trunks wonders what is happening, he is attacked by Bojack knocking him out. Vegeta senses a strong power level and decides to fly to where Future Trunks is, bringing his son's sword along with him. Gohan senses a powerful energy level and flies to the arena where the unconscious Kuririn and Future Trunks lay. Yamcha and Tien try to help take down Bojack's gang, but they are easily taken down by a few hits. Gohan turns into a Super Saiyan and tries to fight them, but he is unsuccessful. He is about to be hit by Bojack's Full Power Energy Ball when Piccolo uses his Special Beam Cannon to deflect it.
Piccolo tries to fight Bojack, but is overwhelmed by his might. Gohan rushes to save him, but before Bojack could finish Piccolo, Future Trunks intervenes by shooting lots of ki blasts, Bojack protected himself with the Psycho Barrier, Future Trunks decided to charge at him head-on, but was intercepted by Bujin's psychic threads, which drains him of his energy, causing him to revert to his base form as Bido took this opportunity to throw a sharpened metal piece at Future Trunks, Vegeta saves him by throwing Future Trunks' sword in the way of the sharpened projectile. Future Trunks swiftly caught his sword, and sheath and equipped himself. With only Gohan, Vegeta, and Future Trunks left fighting Bojack and his gang, Vegeta and Bojack were shooting Ki Blasts at each other only to outmatch Vegeta. Future Trunks rushes to save him, but was intercepted by Zangya and Bujin.
Vegeta is later taken down by Bojack when he transformed, while Future Trunks is getting beaten by Zangya (thanks to Bujin's psychic threads to hold him in place) and is later knocked out by Bojack's Galactic Blow to his chest. Eventually, Gohan is the only one left fighting. He tries to fight Bojack and his gang, however, Bojack is so powerful that Gohan is almost killed. Even though Mr. Satan tries to flee the island, he is sent by the audience to fight the aliens, and accidentally helps Gohan out of a tight spot, but Bojack fires a Ki Blast causing Mr. Satan to fall to the ground.
Bojack proceeds to squeeze Gohan to death, also saying that he wants to thank Goku for freeing them and that killing Gohan would give him the message. Goku is angry of what is happening to his son, even asking King Kai if there is something to do, to which King Kai only replies by shaking his head. Je screams in pain only to show his teammates out cold. After all seems lost, Goku breaks the rules and uses Instant Transmission for a very short moment to free Gohan from Bojack's grasp. After this, he talks with his son and then goes right back to the Other World.
Goku's words of encouragement give Gohan the power he needs to stand up to Bojack and his men. Gohan once again transforms into Super Saiyan 2 and unleashes his power. Bojack commanded Bujin and Bido to use their psychic threads to hold him in place, only to find out that it Gohan is now unaffected by the technique. Gohan kills Bido and Bujin each in one hit. Bojack is desperate and Zangya is frozen in fear of Gohan's unleashed power. As Gohan charges at them, Bojack kills Zangya by shooting an energy blast through her to kill Gohan. Gohan dodges the attack and stamps his fist into Bojack's stomach out of his back. As a last duel, Bojack powers up his Galactic Buster and Gohan prepares his Super Kamehameha. The energies clash together, creating a blinding light through the street. In the blinding light, Gohan and Bojack go headfirst into each other, and Gohan punches Bojack clean through his stomach, killing him.
Gohan, Future Trunks, and Kuririn are at the hospital, healing from their injuries. The news says that it is Mr. Satan who saved the Earth, so Kuririn and Oolong makes fun of Mr. Satan about how he gets credit for saving the world while they are at the hospital too, and say other things about him in general. The movie ends with Piccolo and Vegeta shown on top of the roof in isolation.
- Masako Nozawa as Son Goku & Son Gohan
- Mayumi Tanaka as Kuririn
- Toshio Furukawa as Piccolo
- Ryo Horikawa as Vegeta
- Toru Furuya as Yamcha
- the late Hirotaka Suzuoki as Tien
- Hiroko Emori as Chaozu & Bujin aka Monty Cash
- Takeshi Kusao as Future Trunks
- the late Hiromi Tsuru as Bulma, Baby Trunks & Mrs. Cash
- Naoko Watanabe as Chi-Chi
- Naoki Tatsuta as Oolong, Bujin, X.S. Cash, Doskoi & Bubbles
- the late Kohei Miyauchi as Master Roshi & Udo
- the late Daisuke Gori as Mr. Satan
- Tessho Genda as Bojack
- Hisao Egawa as Bido
- Tomoko Maruo as Zangya
- Toshiyuki Morikawa as Gokua
- Iemasa Kayumi as Gyosan Money
- Joji Yanami as King Kai & the Narrator
- Sean Schemmel as Goku & King Kai
- Stephanie Nadolny as Gohan & Baby Trunks
- Christopher Sabat as Piccolo, Yamcha & Vegeta
- Sonny Strait as Kuririn
- John Burgmeier as Tien
- Eric Vale as Future Trunks
- Monika Antonelli as Chaozu
- Tiffany Vollmer as Bulma
- Cynthia Cranz as Chi-Chi
- Mike McFarland as Master Roshi
- Brad Jackson as Oolong & Doskoi
- Chris Rager as Mr. Satan
- Christopher Bevins as Bujin
- Robert McCollum as Bido
- Colleen Clinkenbeard as Zangya & Monty Cash
- Iman Nademzadeh as Kogu
- Bob Carter as Bojack
- Grant James as X.S. Cash
- Jamie Marchi as Mrs. Cash
- Brice Armstrong as Udo
- Kyle Hebert as the Narrator
- This film was Stephanie Nadolny's final film performance as Teen Gohan.
- This was the last movie for Japanese voice actor, Kohei Miyauchi, who died two years later. He was well known for playing Master Roshi. Some of his voice over work that he completed as Master Roshi was release after he died.
- The poster for the movie shows Goku using the Kamehameha, but he does not use it at all in the movie.
- During the early parts of the tournament, Sky Dragon can be seen. This character comes from the Dragon Ball filler episode "Goku vs. Sky Dragon", making him a rare example of a filler character from Dragon Ball appearing in Dragon Ball Z. Similarly, a fighter similar to Man-Wolf is also seen fighting in the tournament.
- During the early portion of the movie, at the first part of the tournament, a person in the stands can be seen wearing a shirt that says "The Super Saiyan" on it.
- The way that Master Roshi identified females in this movie parodied the Terminator. Text is also clearly visible in his glasses.
- At the end of the preliminary round, when Piccolo wins, the announcer says that he has advanced to the semi finals but Piccolo had advanced to the quarter finals.
- The cards in the Other World had Emperor Pilaf, Mai, and Shu on them. Along with a brief Frieza Saga flashback Bulma has, this is one of their two brief cameo in Dragon Ball Z.
- Similar to Dragon Ball Z movie 7, this is one of the few movies to have a swear uttered by one of the characters retained in the English version (Future Trunks exclaims "What the hell are you?!" when encountering Kogu). Both movies also end with Piccolo and Vegeta in isolation, with the two shown on the roof of the hospital this time.
- In the manga and anime episode, Future Trunks is last seen with short hair, but it is long again in the movie. It is possible that Future Trunks spent a year or so in his timeline helping to rebuild society and then returned to the present timeline, which would explain his hair being longer.
- Kogu and Zangya were never referred to by name during the whole movie.
- The 18th Shunsuke Kikuchi music package for the franchise starts here. The cues were designated "M16XX" codes, and this package would make its series debut in Gohan Goes to High School.
- In this movie, an anime character with a deep red Mohawk and sideburns, as well a stern look with diagonal scar going across his face appears in the crowd as Space Pirate Captain Harlock.
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