One day, cards began to fall from the sky and were picked up by kids all over the world. The cards featured different characters, different environments, and different powers. Kids created a popular battle game not knowing that these cards actually corresponded to an alternate world called Vestroia. Kids from all over the world played with the cards, yet 6 kids stood out: Dan, Marucho, Runo, Shun, Julie and Alice. They named the monsters Bakugans and their elite team the Bakugan Battle Brawlers.
Vestroia is a vast dimension comprised of 6 attribute worlds: Fire, Earth, Light, Darkness, Water and Wind. At the very centre of this universe there are two opposing energy cores; THE INFINITY CORE, the source of all positive energy and THE SILENT CORE, the source of all negative energy. Throughout history, these two opposing forces had maintained the balance of equilibrium in Vestroia.
However, there was one rogue Bakugan who lusted for control, and schemed to seize all of the power for himself. His name was Naga and his mission was to penetrate the silent core and seize its power.
Meanwhile, back on Earth a scientist named Michael had been working on a dimension transportation device. During testing of the machine, an explosion sucked him in and led him to Vestroia where he discovered the two energy cores. While trying to return to earth, he was pulled in by the evil energy of the Silent Core and became the villain known as Hal G. While in Vestroia, Hal G encountered the Bakugan Naga, and the two made a deal - Hal G would give Naga the human world in exchange for his control over Vestroia!
Naga eventually succeeded in his goal of reaching the silent core and began to absorb its negative energy. However, the negative energy proved too much for Naga to handle. The negative energy exploded and the Infinity Core fell to earth. Vestroia erupted in pandemonium; the negative power overwhelming the minds and wills of the Bakugan who live there.
As Vestroia begun to collapse, the human world is also affected. The Infinity Core and the Silent Core are interfering with one another and starting to run wild. Now it is up to Dan and the other Battle Brawlers to find the Infinity Core and reunite it with the Silent Core to restore balance. What these young warriors initially thought was just a game has become a race to restore peace throughout the universe!