Ash and friends arrive on Mt. Coronet where Ash engages in a battle with a boy named Alan and his Nosepass. When the battle leaves the mountain, Alan says they must stay on the mountain in order for Nosepass to evolve. Eventually, Nosepass evolves into Probopass. Before the battle can continue, Team Rocket arrives and puts a device on Probopass, which turns it against Alan, and allows it to go with them. Team Rocket plans to make more controlling helments in order to gain an army of Probopass. Meanwhile, Ash and the others begin formulating a plan to get Probopass back.
Ash battles Alan, using his Turtwig to battle a Nosepass. Nosepass uses Zap Cannon, but Turtwig evades. Nosepass uses Zap Cannon, but Turtwig dodges and charges. However, Turtwig passes Nosepass, so Nosepass goes after it. Nosepass still misses firing a Zap Cannon. One attack does affect Turtwig, but it manages to go on a safe zone. Alan now stops the battle, as he plans to evolve Nosepass to Probopass, which requires Nosepass to be under the zone where it is able to evolve, as it cannot evolve elsewhere. So, they continue their battle.
Nosepass uses Rock Slide, using a rock and making it fall down on Turtwig, but it manages to evade. Turtwig tackles Nosepass, so Nosepass does the same to Turtwig. Turtwig and Nosepass tackle each other. Suddenly, Nosepass evolves to Probopass. Ash still wants to end the battle, but something came on Probopass' head and the mini-noses go up and attack Alan. Team Rocket caused this event, so they control the mini-noses. Alan tells what they worked on, but Ash falls down on him to prevent damage. The ground shakes and cracks, and Team Rocket depart away with Probopass. Alan recalls his memories with Nosepass and now it is stolen. The heroes tell him to remember the burning spirit, making him confident once more.
Team Rocket are elsewhere - Jessie lounges, while Meowth and James set the antannae for more Probopass to be captured. James complains how Jessie does not work, but Meowth reminds him they could conquer the world... so James works faster. The heroes search and Brock reminds them the antenna and the remote control need to be smashed. He spots that the compass' needle moved, so Probopass is near. They spot more antennae are being made, so Alan goes to get them. Brock stops him, as it would be dangerous and instead, Ash sends Buizel. While Meowth sees the Probopass and thinks how it could be used for the boss, Buizel splashes him and hides back in the water. Buizel splashes Jessie, who is angry and thinks her team mates did it. Meanwhile, Buizel drops the remote control, but gets detected.
Buizel goes back, but gets confused by Dustox's Psybeam. Wobbuffet pulls the remote control, but this causes Probopass to act. Alan goes to get it, while Ash sends Staravia, who pushes the control away. Ash goes to get the control, but falls in the river, as Dustox used Whirlwind. The remote control explodes on Probopass' antenna, causing frenzy - the mini-noses destroy the antennae and the remote controls, then blasts Team Rocket off with Zap Cannon. Probopass goes to attack everything, so to prevent recklessness, Pikachu uses Thunderbolt and Probopass re-gains control... for a moment, as it uses Zap Cannon, attacking everything.
The heroes go after Probopass. Buizel's Water Gun slows it down, as Alan charges and goes to get the antenna off. Despite the warnings, Alan orders Ash that Pikachu uses Thunderbolt, so he does that, electrocuting them both. This did not work, so he pleads again. Dawn sends Pachirisu as support. With Alan's signal, Buizel uses Water Gun, Pikachu Thunderbolt and Pachirisu Discharge to hit both of them. Alan and Probopass fall from the cliff in a lake. Still, Alan manages to take the antenna off. Buizel goes in the lake, while the heroes go take care of Team Rocket. Pikachu uses Thunderbolt, but Meowth throws a net, which prevents electricity from attacking them, while the heroes are electrocuted.
Alan managed to get Probopass its control back and swims to shore. Alan and Probopass come out of water, so Jessie sends Seviper and James Carnivine. Buizel frees the heroes using SonicBoom to get the net off. Seviper uses Poison Tail and Carnivine goes to bite, but get attacked by Magnet Bomb, which hits Team Rocket and hits them. Pikachu defeats Seviper and Carnivine with Volt Tackle, and with Probopass' Zap Cannon and Pachirisu's Discharge, Team Rocket are sent away blasting off. Ash is glad for Alan's victory, but still have a battle. Turtwig and Probopass tackle each other. Dawn sees there is a lot of spirit, but without it, they wouldn't be the same.
- Professor Oak's lecture: Shieldon
- Pokémon senryū: うけとめろ かおでぼうぎょだ タテトプス Uketomeru, kao de bōgyo da, Tatetopusu.
- Pokémon Symphonic Medley was used as background music.
- The dub's title is a reference to the song "She'll Be Coming 'Round the Mountain".
- This is the first episode of the anime to mention location-based evolution which was introduced in the Generation IV games.
- This is one of the few episodes of the Diamond & Pearl series where Dawn's Piplup does not appear.
- In the opening scene where Turtwig battles Nosepass, Turtwig's Japanese voice can be heard over its English voice.
- This episode takes place while Ash and his friends are traveling from Hearthome City to Solaceon Town; however, Mt. Coronet is not found between those two settlements.