It is said that hundreds of years ago, the Guardian of the Aura, Aaron, used the power of the Tree of Beginning to stop a great battle.

Now, the town gathers at Camaron Palace for a festival celebrating this hero and Ash and friends have arrived just in time to participate! Ash and Pikachu compete--and win--the Pokemon Battle Contest, becoming this year's honorary Guardian of the Aura.

However, when they're set to celebrate Ash and Pikachu's great victory, the Legendary Psychic-type Pokemon Mew arrives--taking Pikachu away! And that's only the beginning, because suddenly the Guardian of the Aura Pokemon, Lucario, awakens--bringing Ash along on its journey to find the Tree of Beginning!

Where is Pikachu and why has Mew taken it? Why has Lucario awakened? What is the secret behind the Legend of the Guardian of the Aura? Ash is about to uncover the answers to these questions and more, in the latest and most mysterious Pokemon adventure yet!