As the Twinleaf Town Festival continues, Ash and friends are surprised when they find that one of the upcoming Pokémon courses is to be hosted by none other than Professor Oak. Trouble starts brewing, however, when James brings back an old plan: to disguise himself as the professor.

Ash and friends find out that the main event for the Twinleaf Town Festival is a battle tournament, and the winner gets to have a battle with the Sinnoh Battle Frontier Brain, Palmer. Excited about that, Ash enters the tournament with hopes of battling him.