Masquerade has been destroying kids’ Bakugans all over the world and the Brawlers need to put a stop to it. Reluctantly, Dan joins Runo and Marucho in another attempt to recruit Shun. When they arrive at Shun’s home, Masquerade is already there! They can’t believe that Shun is on Masquerade's side. Dan accepts the challenge of a battle and together with his Bakugan Drago, goes up against Shun and Masquerade. Will Shun send Drago to the doom dimension or will his old friendship with Dan convince him to turn on Masquerade?

Lured by an invitation to celebrate their world class rankings, five of the top ten Bakugan players gather at a mysterious mansion. There they meet Masquerade and the evil Bakugan “Naga”. They are put under a spell to take Dan and the other Battle Brawlers out of the picture. Meanwhile, Alice confesses that she believes her grandfather Michael had something to do with the destruction of Vestroia. The brawlers decide to visit Dr. Michael’s lab and find evidence of what happened to him. But there are still many unanswered questions…