The moment Goku and Vegeta realize they have to fuse is the moment the movie knows exactly what it's selling: not a new villain, but permission to see these two finally work together instead of against each other. Janemba is just the excuse. The real spectacle is watching the franchise's two biggest egos stop arguing and become something neither could alone. It's a power fantasy dressed up as a villain fight, and it costs the movie nothing because fusion has always been the fantasy fans wanted to see.

When a young demon neglects his job, an evil cleansing machine in the afterlife overflows and explodes, turning him into the monster Janemba. As Janemba spreads havoc across the realm of the dead, Goku, who has been fighting in martial arts tournaments for the deceased since dying in the battle against Cell, heads toward the trouble alongside fellow fighter Pikkon. Janemba soon transforms into a sword-wielding foe stronger than anyone Goku has met. Goku and his rival Vegeta each try to beat the monster alone, then realize fusion is their only option before Janemba tears apart the fabric of the universe. The film is a sci-fi action adventure.