Pokémon: Lucario and the Mystery of Mew 2005

In ages long past, a looming war brews beyond the Tree of Beginning. The aura-wielding Lucario warns his master, the Aura Guardian Sir Aaron, of the coming danger, but Aaron betrays him and seals Lucario inside a staff. The staff is passed to the Queen of Cameron Palace by a Pidgeot, and when the Tree of Beginning begins to glow brilliantly, the looming conflict is halted.

Centuries later, Ash Ketchum and his friends arrive at Cameron Palace for a festival honoring Sir Aaron. Ash, wearing a replica of Aaron’s outfit, enters a tournament and wins, earning the title of Aura Guardian for the year. As part of the celebration, Ash is granted Aaron’s staff, and his aura—resembling Aaron’s—unintentionally frees Lucario from his long imprisonment. After the release, Lucario informs everyone of Aaron’s betrayal.

Meanwhile, Pikachu Pikachu and the other Pokémon are playing with a Mew near the palace, when a pair of Weavile, sent by the adventurer Kid Summers to track Mew, chase them. Pikachu protects Mew and teleports it away, along with Meowth from Team Rocket. Ash and the group learn that Mew has taken them to the Tree of Beginning, where Mew resides, and Kid Summers agrees to help, seeking Lucario’s aid as their guide.

On the journey, Lucario recalls the past through time flowers that reveal Aaron’s history and the moment of his capture. Max, Ash’s young companion, offers Lucario a chocolate bar, which helps him begin to trust humans. With Lucario’s hesitant acceptance, the group presses on toward the Tree of Beginning.

They confront the tree’s guardians—Regirock, Regice, and Registeel—as they near the tree’s heart. Inside, the tree’s antibody-like defense system traps everyone, and Pikachu pleads with Mew. Mew uses its bond with the tree to calm the defenses, but the disruption of energy leaves Mew gravely ill, threatening the tree’s life. They reach the tree’s heart, where a time flower reveals Aaron’s sacrifice: he used his Aura to seal himself away and stop the war.

Ash and Lucario fuse their auras to reverse the tree’s self-destruction and save Mew, though Lucario pushes Ash aside at the crucial moment to allow the ritual to complete. After the Tree is restored, Lucario finds one last time flower and sees a vision of the dying Aaron, learning that his master sealed him away to spare him and thanking him for their friendship. Lucario passes away peacefully. Kidd and Ash reunite with their teams, and Kid Summers decides to keep the discovery secret while Ash vows to honor Lucario’s memory.