Episode #258 - A Crowning Achievement
Ash and friends are still heading for Mount Silver. Misty tries talking to Larvitar, but it Hardens as usual. Brock tries to relax it by making funny faces, but it gets upset. Once Larvitar has calmed down, they decide to stop by a nearby waterfall for lunch.
Team Rocket watches them and plans to steal their Pokemon. Ash hears the waterfall and runs toward the sound, but slides down a hill. At the bottom is a lake with many Slowpoke around. Misty can tell that the lake used to be deeper, and the Slowpoke don't look happy. Sitting on a large boulder in the middle of the lake is a King's Rock. Two rangers approach and call out to the kids to not touch the King's Rock, and they'll explain why if this place is kept secret.
The two introduce themselves as Alice and her father Professor Telasu. Alice has a Slowpoke called Arthur. Brock flirts with Alice and Misty drags him away by the ear.
Team Rocket listens to the conversation and figure that the King's Rock would be worth a lot of money if they can steal it.
The professor leads them all around the lake while Alice explains that an earthquake several years before caused most of the water to drain away. What's left isn't enough for the wildlife in the area. Soon they reach a rock wall covered with ancient drawings that had been made by natives long ago, and were uncovered when the water receded.
The drawings tell a story of how the lake once dried up, and the Slowpoke were saved by one Slowpoke who put on the King's Rock and evolved into a Slowking. Brock notes that Slowpoke have a branched evolution: they can evolve either into Slowbro or Slowking. What's exciting is that now the same situation is happening again, so they expect a Slowpoke to step forward and become a Slowking sometime soon.
Team Rocket appears and threatens to steal the King's Rock. They attack with their Pokemon, but Ash and Pikachu are ready. When Pikachu runs into trouble, Larvitar gets upset and Screeches, stunning everyone. For some reason the Screech attack doesn't affect Arthur, and it calms Larvitar down. Brock releases his Forretress and stops TR from grabbing the King's Rock, and Pikachu sends them blasting off.
The professor is worried that soon the lake will be completely dry and the Slowpoke will have nowhere to go. The only hope is for a Slowpoke to evolve, but every time one tries it gets attacked by a Shellder and becomes a Slowbro. Once that happens it can't go back. Suddenly, Arthur decides to head for the King's Rock, ignoring Alice's calls to return. Shellder attack from all sides, but thanks to a Screech from Larvitar, he manages to shake them all off! Eventually he makes it to the boulder, picks up the King's Rock and evolves!
Team Rocket watches from their balloon, and plan to steal Slowking for the boss. They drop a net onto Arthur, but his powerful Confusion attacks send them crashing into a cliff face. The angry Shellder descend on them, then Pikachu sends them blasting off a second time.
Arthur uses his powers to part the waterfall, revealing a cave behind it. He leads the Slowpoke and the kids through the caves into they reach a large underground lake. The Slowpoke will be happy here. The humans go back outside, and Alice bids a tearful farewell to her friend before he disappears behind the waterfall.
Alice and her father will keep watch over this place so others won't discover the secret. Ash and his friends depart.