Pokémon Season 4 Episode 22

Catching a sweet scent on the breeze, Ash and Pikachu follow their noses to a nearby apple orchard. As Misty and Brock follow, they warn the trainer and his Pokémon against eating apples that don't belong to them. No sooner is this said than Pikachu is caught red-handed with couple of cores! Once Ash proves Pikachu's innocence to the orchard owner, he and Pikachu track down the real thieves.