Pikachu became Ash Ketchum’s first partner in the original Pokémon animated series.
In the opening episode, Ash arrives late to Professor Oak’s laboratory and finds that the traditional starter Pokémon—Bulbasaur, Charmander, and Squirtle—have already been chosen. Professor Oak gives him Pikachu instead. Pikachu initially resists Ash’s commands and refuses to stay inside its Poké Ball.
Their relationship changes after Ash risks himself to protect Pikachu from wild Spearow. Pikachu then uses its electrical power to defend Ash, establishing the friendship that drives the television series. Although Pikachu is not one of the three standard starter choices from the original games, the anime made it the franchise’s most recognizable character.
Viewers sometimes confuse Ash’s anime partner with the player’s possible first Pokémon in Pokémon Red, Green, or Blue. In those games, the player chooses Bulbasaur, Charmander, or Squirtle. Pikachu is instead Ash’s signature partner in the animated continuity, and its distinctive voice was performed by Ikue Ōtani in the Japanese version.