Ep 4. The Bug Stops Here

Ash, Misty, and Brock are still traveling through Johto, and they've arrived in Azalea Town. The town is famous for its Slowpokes and for the Slowpoke Well, located at the outskirts of the town which Ash and his friends have become interested to explore. When they get to the well, they find Team Rocket, who have trapped a group of Slowpoke. The trio tries to steal the Slowpoke, but Ash and his friends stand up to them.

The battle that ensues between Team Rocket and Ash and his friends is interrupted by the arrival of a young boy named Bug Catcher Jimmy. Jimmy is there to catch a Pokémon that has made its home in the Slowpoke Well, and he's willing to do whatever it takes to capture it. Ash and his friends decide to help him out, and they all venture deeper into the well.

As they explore the well, they're confronted by all sorts of Bug-type Pokémon, including Weedle, Caterpie, and Kakuna. They eventually find the Pokémon that Jimmy is after: a Scyther. The Scyther is far too powerful for Jimmy, but Ash's Pikachu manages to weaken it enough for Jimmy to capture it. However, when they try to exit the well, they find that Team Rocket has blocked the exit with a boulder.

Jimmy's love of Bug-type Pokémon turns out to be more than just a casual interest: he's actually the apprentice of the legendary Bug-type Pokémon trainer, Bugsy. Bugsy is the leader of the Azalea Town Gym and has a reputation as one of the strongest trainers in Johto. Together, they come up with a plan to lure out Team Rocket, who have set up a base inside the well.

They employ the help of all the Bug-type Pokémon in the well to create a diversion, giving Ash and his friends the opportunity to break through the blockade and escape. The diversion works, and they all manage to make it out of the well safely.

In the end, Jimmy issues a challenge to Ash to battle his mentor, Bugsy. Ash accepts the challenge, and the episode ends with the two trainers facing off in an intense Pokémon battle.