King Kai Joji Yanami senses the collapse of a southern galaxy at the hands of a mysterious Super Saiyan and warns that the north could be next. From his celestial post, he reaches out to Goku Masako Nozawa, urging him to track the legendary power across the stars and follow the tremors of a threat that grows with every passing moment.
On Earth, an ordinary picnic is disrupted when a spaceship lands and Vegeta Ryo Horikawa faces off against Paragus Iemasa Kayumi, a Saian warrior who claims to have forged a new Saiyan world and demands Vegeta's ascent to the throne. Paragus warns that the so‑called Legendary Super Saiyan is ravaging the galaxy and must be stopped. With a resolve sharpened by this revelation, Vegeta agrees, and he is joined by Gohan Masako Nozawa, Future Trunks Takeshi Kusao, Krillin Mayumi Tanaka, Master Roshi Kohei Miyauchi and Oolong Naoki Tatsuta as they board Paragus’s ship to pursue the coming danger.
On New Vegeta, Vegeta encounters Paragus’s son, Broly Bin Shimada — a figure whose raw power unsettles even the seasoned prince. Broly joins the hunt for the Legendary Super Saiyan, and Gohan, Krillin, and the others begin to explore the planet, discovering that it is deserted except for enslaved aliens who recount a civilization erased by a superior foe. The masters among them abuse their captives, but Gohan and Krillin drive them back. Soon after, Goku arrives and is greeted by Paragus, who recognizes him as Bardock’s son and invites the group to a meal at the palace. Broly’s agitation spikes at Goku’s presence, and Paragus moves to control his son with a device on his bracelet, synced to a headband. Yet Broly’s aggression breaks through the mind control, and the danger escalates as Paragus theorizes that Broly’s feral Saiyan instincts are stirred by Goku’s power. He recalls that they were born on the same day, a coincidence that fuels their shared fate.
Goku and the others confront Paragus upon learning the truth about Broly, and the mind control device falters as Broly’s rage intensifies. Broly breaks free and transforms into the feared Creative force known as the Legendary Super Saiyan, unleashing a torrent of power. Goku, Krillin, and Gohan brace for impact as Broly’s assault threatens everyone present, and Vegeta—normally fearless—finds himself overwhelmed by the onslaught. Paragus goads Vegeta while revealing a brutal history: Broly was born with a power level around 10,000, and King Vegeta ordered his execution to prevent a royal catastrophe. Though Paragus’s plan was to use Broly against Vegeta’s bloodline and to turn Earth into a new Planet Vegeta, fate twists as the two Saiyans collide with the planet’s doom looming large.
Piccolo arrives, bringing Senzu Beans to heal Goku and his allies, who were overwhelmed by Broly’s unstoppable force. With Piccolo’s aid, the team regroups and mounts a renewed effort to challenge the Legendary Super Saiyan. Goku, bolstered by the support of his friends, calls for help from them to lend their ki, a request that tests each warrior’s pride and resolve. Vegeta, after a display of stubborn reluctance, finally yields his energy to Goku, who channels it into a decisive blow that destabilizes Broly’s power. The Legendary Super Saiyan’s might collapses just as a comet hurtles toward New Vegeta, and the heroes brace for impact.
In a final, desperate bid, Goku and his comrades—alongside the freed slaves—evacuate the doomed world, escaping aboard Piccolo’s ship as the comet draws near. The moment of peril gives way to relief as they pull away from New Vegeta and set course back toward Earth, hearts buoyed by their survival and the knowledge that the battle has ended, at least for now, with the victory of unity over a power that could have rewritten the fate of many civilizations.
