Ash and N: A Clash of Ideals! (Japanese: 白の遺跡!サトシ対N!!The White Ruins! Satoshi VS N!!) is the 120th episode of the Best Wishes series, and the 777th episode of the Pokémon anime. It first aired in Japan on April 4, 2013 and in the United States on July 6, 2013.
Spoiler warning: this article may contain major plot or ending details.
Outside Dragonspiral Tower, Ash, Cilan, and Iris meet Professor Cedric Juniper’s assistant Nick, who offers them a ride to meet the professor at the White Ruins. En route, he tells them the excavation team may have made a fantastic discovery, but won’t say any more.
Inside the ruins, our heroes are reunited with Cedric, who shows them a door covered in mysterious symbols. He moves a few panels around, and the door comes open! There, in front of their awestruck eyes, is the Light Stone—an item straight out of legend that is said to be Reshiram in a different form! The professor picks up the stone, and it bursts into flame in his hands, sending a bright blast of light straight up into the air and leaving him unharmed.
From a distance, N sees the light and senses Reshiram’s presence. He makes his way to the ruins, surprising Professor Juniper and the others, and demands to know what the professor plans to do with the stone. Cedric explains that the Light Stone and Reshiram are part of his life’s work, and says he plans to investigate the stone thoroughly. N finds this unacceptable and leaps into action, grabbing the case with the stone in it and running away. Ash chases after him, but the ground gives way under his feet. N goes back to help him—even dropping the case to grab Ash’s hand—but finds himself falling as well, and the two of them land on soft sand deep underground.
Back on the surface, the others are trying to figure out how to get Ash and N out when they get some unexpected visitors: Team Plasma! The villains also saw the blast of light from the stone and followed it to the ruins, planning to get their hands on both N and the Light Stone. They’re prepared to attack Iris, Cilan, and Cedric when Nick reveals his true identity: it’s Looker, from the International Police! He corners Team Plasma’s Aldith and says reinforcements are on their way, but Colress activates his now perfected machine and takes control of the Golurk who have been helping with the excavation, turning them against our heroes!
Jessie, James, and Meowth have tracked Team Plasma to the site, but they decide to sit back and wait for the dust to settle before leaping in to steal the Light Stone and Pikachu. Underground, N and Ash are having an intense conversation about the relationships between people and Pokémon. N still thinks Pokémon would be better off without people, but Ash insists that he just wants to learn more about Pokémon and be really good friends with them—including Reshiram!
Then the two hear the sounds of battle above them and decide they have to find a way out. Who will claim the Light Stone when this battle is over?
Plot
This plot summary is incomplete. Please feel free to edit this plot summary to add missing sections and complete it.
The gang arrive at White Ruins and meet up with Professor Cedric Juniper. Professor Juniper unearths the Light Stone and tells the gang that it may be Reshiram in a different form. He tells them that he wants to research the Light Stone and puts it into a metal protective case. N arrives and after hearing Professor Juniper's plans, he gets disgusted and snatches the case away from him. He starts to run off while Ash gives chase. Ash falls into a small pit in the stone floor. N turns back and tries to help but winds up falling too and lets go of the Light Stone to grab a hold of Ash's hand. The Light Stone falls out of sight in the pit. The two are dangling from part of the floor where it crumbles off and they fall down into the pit with some stones covering the hole as Cilan, Iris, and Professor. Juniper watch in horror.
Ash awakens in a small cave under the Earth with Pikachu at his side. N appears unharmed and points where the Light Stone has fallen. He and Ash realize there's no way out and decide to wait it out until help arrives. N bonds with Ash and Pikachu while they wait. N tells Ash all about the relationships he seen between people and Pokémon. He tells Ash how he witnessed people treating Pokémon like family and people abandoning their Pokémon leaving them all alone in dark alleys. Ash smiles and tells N that Pokémon are his friends and that he wants to learn more about them.
Meanwhile, Team Plasma attacks Professor Juniper and the others to try to get N and the Light Stone as Team Rocket watch in the shadows.
The chamber where Cedric Juniper finds the Light Stone is highly similar in design to the Relic Castle's appearance in one of the skipped episodes. It is also similar to the chamber where the Golden Dark Stone was found in Explorer's of the Hero's Ruin!.