Jimmy is a guitarist and aspiring Pikachu trainer who showed up in "Battling at Full Volume!" He's got his own Pikachu partner, a scrappy thing he calls Spike, and he's determined to become the strongest trainer with a Pikachu by his side.
He first caught wind of Ash's Pikachu through Team Rocket, which naturally piqued his interest. When he tracked down Ash's campsite, he made a loud entrance—literally blasting an electric guitar to get everyone's attention. He wanted to challenge Ash to a battle right then and there, but Ash was sick in bed, so Serena stepped up instead, disguising herself in his clothes and doing her best deep voice impression. Their match got interrupted when Clemont and Bonnie came back with medicine, but it picked up again soon enough.
Then Team Rocket showed up and snatched both Pikachu, which derailed everything. Once Ash recovered from being nursed back to health by the group, he went after Team Rocket with everyone's help. Jimmy and Ash synced up their Thunderbolt attacks to send the villains blasting off, which was pretty cool. Jimmy gave Serena props for her battle skills after that.
By the end, Ash and Jimmy had agreed to battle each other, though they decided to grab some food first since Ash was starving. They never actually got around to fighting before the episode wrapped.
Content compiled by AnimeList.moe from publicly available sources.
