In the
other world, a teenage
oni is manning a cleansing machine and the loud volume of his
walkman distracts him, causing the machine to explode. The oni is engulfed by the freed evil spirit essence and transforms into Janemba, a massive childlike monster with dimensional manipulation abilities. As a result, the deceased are resurrected.
Goku and Pikkon are fighting in a tournament when they are interrupted by the appearance of a strange crystal-like substance and are sent to investigate the disturbance by the Grand Kai. They find the afterlife's "check-in station" to be encased in the crystal-like barrier which is also immune to their
energy blasts. From inside of the station, its trapped attendant King Yemma directs them to the monster, Janemba, who refuses to drop the barrier. Goku lures Janemba to hell while Pikkon works to free Yemma. Meanwhile, Earth comes under siege by an array of zombies, soldiers and past villains led by
Frieza, who attack a city until
Gohan and
Videl intervene, with the former destroying him causing the villains to flee in terror. The two along with
Bulma,
Goten and
Trunks gather the magical Dragon Balls and summon the dragon
Shenron to ask him to rebuild the barrier between the living and dead, but he is unable to do so since only Yemma can control the boundaries of the afterlife. In hell, Janemba uses his unorthodox powers to best Goku until he powers up to Super Saiyan 3, shaking Other World while he does it, and seemingly kills Janemba. He merely transforms into a much smaller, albeit far more powerful and sinister form - Super Janemba. Goku is overwhelmed by Super Janemba but
Vegeta has regained his physical body and arrives in time to help. However, the two Saiyans are still no match for Super Janemba and are forced to hide. Goku proposes using the Fusion Dance technique, but Vegeta pridefully refuses to join bodies with Goku. Pikkon continues to try and free Yemma to no avail, and in his anger, insults the crystal substance which causes it to slightly crack. However, Pikkon's worst insults do not cause enough damage to rescue Yemma so he decides to aid Goku and Vegeta in their fight. After much persuasion, Vegeta agrees to fuse with Goku but Vegeta fails to extend his forefinger when required and the fusion fails, resulting in a weak,
obese form named Veku. Super Janemba beats Veku severely and almost kills him, but the fusion wears off and Goku and Vegeta escape in time. Pikkon arrives to stall Super Janemba while Goku and Vegeta attempt the fusion again, this time successfully transforming into the immensely powerful Super Gogeta, who swiftly gains the advantage over Janemba and he uses his power to defeat the demon, causing him to revert into his oni form, who flees. With Super Janemba vanquished, his hold over reality disappears and the deceased return to the afterlife. After sharing a good-natured farewell with Goku, Vegeta reverts to his spirit form and disappears. Back on Earth, Gohan, Videl, Goten, and Trunks depart back home. In a
post-credits scene, a still-summoned Shenron awaits another wish. == Cast ==