As they continue exploring the Orange Archipelago, Ash and his friends stumble upon a floating theater called the Pokémon Showboat, where all of the actors, singers, and dancers are Pokémon. The three of them decide to see the show and enter the paddle steamer boat. They watch as Abra referees a boxing ring match between Hitmonchan and Machoke while Clefable watches. As the show comes to an end, Ash says that he guesses there are other Pokémon besides Meowth who can talk.
Suddenly, Togepi wanders off behind the stage. The others run after it and find out that the Pokémon in the performance were lip-syncing to human voice actors hidden backstage. A young actress named Kay appears and yells at the group to be quiet. As the performance ends with the Pokémon dancing on stage, Roger, a voice actor, asks Kay to send her Raichu out to the stage to dance with the other Pokémon. Raichu then appears from behind a box, but when Kay asks it to perform, it sits there sadly and refuses. Ash's group and the voice actors then sail to the next island, Kinnow Island. Ash thanks Roger for taking them along and asks if there is anything they could do in return. He replies that he would like Ash to teach Kay some pointers on how to become closer with her Raichu. Meanwhile, Team Rocket are pursuing the vessel in their Magikarp submarine and plot on stealing the performing Pokémon.
Back on the floating theater, Ash is trying to teach Kay how to get along with her Pokémon. He asks her to show him a performance with her and Raichu, which she does, but Raichu continues to do nothing. Ash then tries to give Raichu some words of encouragement but ends up getting shocked in the process. Later on, Ash tries to talk to Kay about Raichu. Kay blames herself for Raichu not wanting to perform. She explains that when she first met Raichu, the Electric-type approached her, and in its excitement, it nearly shocked her. Kay reacted instinctively and threw Raichu off her and into some crates. Since then, Raichu was too nervous to perform with Kay because it could sense Kay's fears of being shocked again.
Just then, Team Rocket fires two torpedoes at the paddle steamer, which sends Raichu flying into Kay's arms. Raichu starts to shock Kay, but she reassures it, saying that it was okay and that she isn't afraid of being shocked anymore. Team Rocket then appears on the boat. Ash tries to stop them, but Roger insists they comply to avoid destroying the Pokémon Showboat. With everyone tied up, Team Rocket goes to steal the performing Pokémon. As they do, Meowth notices Raichu crying and threatens it, only to get shocked instead. Hitmonchan attempts to intimidate Meowth and James, but upon noticing Roger's eye movements, it pretends to agree with James.
The voice actors manage to get up, even with the ropes still around them, and distract Team Rocket by voicing over their Pokémon. The trick works, and Team Rocket is convinced; Meowth even sympathizes with them, knowing the struggle that talking Pokémon face. The trio soon finds themselves surrounded and are intimidated by the Pokémon's tough talk. Hitmonchan uses Fire Punch and burns James's face. James angrily sends out Victreebel, only for him to get devoured by it. Jessie then sends out James's Weezing and orders a Smokescreen, which chokes everyone on the ship, except for Ash and his friends, who break free from the ropes. James calls back Weezing and the smoke disperses. Ash and Tracey then confront Team Rocket with Pikachu and Marill. Meanwhile, the voice actors have broken free and Kay rushes over to her cowering Raichu. Everyone watches on in amazement as Kay then teams up with her Raichu and uses Mega Punch to blast Team Rocket off the boat.
As the boat stops at another island and prepares for the next show, Ash takes the time to call Professor Oak on the video-telephone about the floating theater. Just then, Kay runs out of the boat and informs Ash that Roger cannot perform in the show because he lost his voice from Team Rocket's earlier Smokescreen. Kay fills in for Roger's part, while Ash, his friends, and their Pokémon join the stage performance.