Pokémon : S3 | E30 – Tricks of the Trade

Ash and his friends walk along Palmpona's waterfront admiring the sea view. They see a young Trainer instructing his Wobbuffet to stand up straight. Ash looks Wobbuffet up on his Pokédex and the boy introduces himself as Benny. He says that he is going to the Pokémon Swap Meet to find someone to trade his Wobbuffet to. Misty wonders why he would want to trade his Pokémon and Benny says he likes Wobbuffet and has trained him hard but now he wants a different Pokémon.

Meanwhile, James waters his Victreebel with a hose while Jessie uses the public taps to clean her face, only to be licked by her Lickitung immediately after. Meowth tells his teammates about the Swap Meet event, and the trio set their sights on stealing some Pokémon, but, unbeknownst to them, Snubbull is following them.
(Source: Bulbapedia)