The group soon discovers that some of the giant Digimon they encounter are not evil Digimon but good Digimon gone bad. A dark power is corrupting even the most gentle of Digimon by embedding Black Gears into them, turning them into vicious monsters. Creating chaos and destruction wherever it goes, the evil power threatens all of Digital World.

As they try to find their way back home, the seven kids are drawn further and further into the mystery. Through teamwork and trust, the digimon digivolve from "In Training" to "Rookie" to "Champions" to "Ultimate" and even to the most powerful form..."Mega" They must save the Digital World from the powerful evil digimons intent on destroying it.

With an unbreakable bond between them, the kids and their Digimon companions embark on the adventure of a lifetime!