Although he's a mainstay of the Pokémon franchise, Ash Ketchum isn't slated to appear in the upcoming Detective Pikachu film. Director Rob Letterman recently explained why the character would be absent and the reasons for choosing to focus on a lesser-known protagonist for the first live-action Pokémon movie.

“The Pokémon Company, they’ve already made many, many movies of Ash, and they came to Legendary with this idea of using a new character," Letterman told IGN.  "So when I came onboard, I was pitched this character of Detective Pikachu, and I fell in love with the story behind it."

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“It’s a really great story," he continued. "It was something with a lot of heart, and it was just very unique. And because there’s already been so much work done with Ash, for the first live-action movie I thought it was a really good idea to try something new with a new character, but bake it into the universe of Pokémon. So it still follows all the rules, and we get to see a lot of our favorite things.”

Adapted from the video game of the same name, Detective Pikachu is slated for release on May 10, 2019. Rob Letterman (Goosebumps) is set to direct the film based on a screenplay by Letterman and Nicole Perlman (Guardians of the Galaxy). The film stars Ryan Reynolds as Detective Pikachu, Justice Smith as Tim Goodman, Ken Watanabe as Detective Yoshida and Kathryn Newton as Lucy Stevens.

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