Pokémon: Indigo League

The Song of Jigglypuff (1x45)

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Ash and his friends find a Jigglypuff in the forest who is too shy to sing its hypnotic song. Brock gives Jigglypuff a fruit that heals its throat to make it able to sing, but Ash, his friends and Team Rocket fall asleep to the song, angering Jigglypuff. Team Rocket tricks Ash and his friends into giving Jigglypuff a stage to perform its song for an audience in Neon Town, whose inhabitants Team Rocket intends to steal from. Everyone falls asleep, including Ash, his friends, and Team Rocket, and a miffed Jigglypuff uses the marker hidden in its microphone to draw on everyone's sleeping faces. From this point on, Jigglypuff follows Ash around trying to sing its song to a crowd that will not fall asleep in almost every episode.