Pokémon: Lucario and the Mystery of Mew, known in Japan as Mew and the Wave-Guiding Hero: Lucario, is the eighth Pokémon movie, and the last to be dubbed by 4Kids before losing the rights to the series.In ancient times of Rota Town in the Kanto region, two armies warred against each other, threatening the safety of all the people who lived there as well. Because of this, a Knight named Sir Aaron, who could use a mysterious power called Aura, and his apprentice, a Pokémon named Lucario, were sent by the queen of Rota to quell the fighting. On their way, Sir Aaron told Lucario that he's leaving the kingdom and never coming back, before sealing Lucario away in his magic staff. Sir Aaron stopped the war and was proclaimed a hero, but no one ever knew what happened to him. Flash forward to the present where Ash Ketchum and friends are visiting Cameran Palace in the middle of Rota Town for a Pokémon tournament. Being The Hero and all, Ash naturally wins, and so is presented with the Staff of Sir Aaron. Because Ash wore a costume identical to Sir Aaron's clothes and Lucario sensed an Aura coming from him, Lucario escaped from the staff, only to wind up distraught by his new surroundings and distrusting of humans. Later that night during a party, a Mew enters the Palace, seeming to want to play, but is then attacked by a mysterious thief. While fleeing, Mew accidentally takes Pikachu (and Meowth) away to a nearby landmark called the Tree of Beginnings. So it's up to Ash and friends, along with Lucario's help, to rescue Pikachu.The film is generally considered among the best of the series, as it makes a breakaway from the mostly derivative plot of the many Pokémon movies by featuring much more engaging characters and story. As of October 2014, it has an IMDb rating of 7.0 out of 10 from 1,593 votes.
The Ace: Kidd. To quote Brock: "Kidd Summers has set a world record for setting the most world records ever a~~~nd, she's soared higher, dived deeper, and space-traveled farther than any human being in history. Kidd's also a surfing expert, a gourmet cook, and a badminton champ. To call Kidd Summers a superwoman is the understatement of the century! She's super-duper!". The only reason Brock knows all of this is because he's her "biggest fan".
Jessie: We're the ones who are supposed to be doing all the stealing.
James: Did you miss the "never to be seen" part?
Famed in Story: Sir Aaron is celebrated as a hero in the present day, though Lucario views him quite differently, due to the fact that the last time he sees Sir Aaron is him apparently abandoning the kingdom in its hour of need.
The Force: Aura is generally an equivalent to this concept, with it existing in all things animate or inanimate, being rarely usable in humans, and Lucario being the only Pokémon capable of sensing and using it.
A little bonus can be found in that Sir Aaron, one of those humans who could use Aura, was a knight while he was alive.
Four Is Death: The four Time Flowers the gang finds. The first shows Ash falling down the mountain after grabbing it, the second shows a vision of the stampeding armies and Lucario being sealed in the staff, the third shows Sir Aaron giving Mew his Aura, and the fourth delivers Sir Aaron's final words.
Identical Granddaughter: Apparent with Lady Ilene, to the point where Lucario mistakes her for her ancestor Lady Rin.
Implacable Mons: The Regis. They're virtually unfazed by the many attacks thrown at them and continue to pursue the heroes until Mew saves all the trainers from the Tree of Beginning. Especially impressive is the fact that they do this despite Lucario attacking them with Aura Spherenote which is super-effective on them, and should have totally WTFpwned Regice in particular due to its low Defense; Aura Sphere would have been physical in the 3rd gen if it had existed back then every time they show up.
Intellectual Animal: Lucario, like some of his other movie Pokémon companions, can communicate with humans via telepathy.
Missing Trailer Scene: One of the trailers involved scenes such as Kid apparently attempting to drive her jeep through the hot springs, Lucario going into some kind of alternate dimension, and a scene in a rocky area with Ash and Lucario. Ash is kneeling with a scared look on his face while reaching towards Lucario, who is lying on the ground, apparently dead from unknown causes.
Mistaken Identity: When Lucario is first set free, he initially believes Ash is Sir Aaron because their Aura is the same. Not knowing this at the time, Ash believed the mistake was due to wearing an outfit similar to Aaron's.
Never Say "Die": Played straight with a human and then immediately averted with the 'tree' and Pokémon.
Kidd Summers: You'll end up destroying yourself!
Ash: If I don't do this, the Tree will die, and so will the Pokémon who live here!
Poor Communication Kills: They could have called this Poor Communication Kills: the Movie. The whole ordeal is set into motion by Kidd and co., none of whom had any ill intent and all of whom know when to leave major natural phenomena alone as soon as they know they should, but just came off as a bit too aggressive at first. Note that Mew, being psychic, probably would have been able to sense this had it not been busy getting walloped by a pair of overenthusiastic Weavile. Mew, who keep in mind is a kleptomaniac, runs off with Pikachu and Meowth in a panic — and neglects to bring them back or let anyone know they're okay at all. Ash, who at this point has every right to fear the worst, stages a rescue attempt that triggers a Diabolus Ex Machina that eats most of the cast. Said Diabolus's reversal nearly kills everyone, and does cause one of the only real deaths in the series — someone who was totally innocent of the fiasco.
Additionally, when Sir Aaron sealed away Lucario, he failed to properly explain why he did so, leading Lucario to believe that he'd betrayed the kingdom and causing Lucario to distrust humans until he eventually finds out about Aaron's Heroic Sacrifice. This however was intentional, as he didn't want Lucario to come and experience the same fate as he did.
The Promise: When Ash tries to console Lucario after it believes it was abandoned and asks if he can help, it only wants him to do one thing: Promise he will never abandon Pikachu. Ash swears he will not.
Rescue Arc: Although, ironically, Pikachu wasn't in any real danger until the cavalry arrived and set off traps.
Ret Gone: Inverted. A painting displayed in the palace shows Sir Aaron alone. During the end credits, when the heroes return to the palace, they find that the painting now shows Lucario standing next to Sir Aaron.
Samus is a Girl: Kidd, in knight costume. In-universe as well, seeing how Ash and company reacted when she took her helmet off.
Sealed Badass in a Can: Sir Aaron seals Lucario into his staff and leaves him there. Flash-forward to the present, and Ash's aura allows him to be released.
Seeker White Blood Cells: The orange blobs within the tree are described as its equivalent to white blood cells. They specifically home in on any nearby humans.
Shout-Out: the fact that the two warring armies are Red and Green is a direct reference to the original two Pokémon games.
Synchronization: Mew and the tree seen to be linked together in this way, as disabling the tree's Seeker White Blood Cells seems to disable his own immune system, causing him to become sick almost instantly which in turn causes the tree to start dying.
Tagalong Kid: the wild Bonsly, which had no relevance to the plot whatsoever.
Chekhov's Gunman: In the end credits, Bonsly is shown playing with Mew, implying that Mew has a new friend that it can play with without, you know, kidnapping one.
Took a Level in Badass: Ash is at his best in this movie, considering that he almost made a conscious Heroic Sacrifice to save all the Pokémon living under the Tree of Beginning - only to be stopped by Lucario.