In the legendary past, an aura-guiding hero Pokemon named Lucario sansed the presence of two armies who were about to fight at Cameron Palace in Kanto. Lucario's master Sir Aaron runs away from the kingdom while it's people fight the war and go to the Tree of Beginning. Abandoning the queen, Sir Aaron sacrifices himself with Lucario's aura to stop the war. Many years later, Ash and his friends are at Cameron Castle for the annual festival celebrating King Aaron's life. After winning a contest, Ash gets to hold the same staff used by King Aaron. With a very similar aura to King Aaron, Lucario is summoned by Ash and immidiately begins searching for answers as to why he was sealed away. He soon finds along with Ash that a female trainer named Kidd, who Ash had previously befriended, is out to steal a Mew to disrupt an old legend from King Aaron's time. Released to Japanese theaters in 2005, the movie was released direct-to-video in the U.S. in 2006.