Rick Riordan, the author behind the Percy Jackson series, penned a scathing response to racist complaints about Leah Jeffries being cast in Percy Jackson and the Olympians.

Variety broke the news that the 12-year-old will play Annabeth Chase in the upcoming Disney+ series, which also stars Walker Scobell as Percy Jackson and Aryan Simhadri as Grover Underwood. The character was played by Alexandra Daddario in the series' 2010 and 2013 big-screen adaptations.

Jeffries celebrated the happy casting news with a jubilant post on Instagram. "I'm so excited to take on the role of 'ANNABETH,'" she wrote. Check out her announcement below:

Meanwhile, some fans of the series took to social media to complain that Jeffries, who is Black, does not match the description of the character in the books or movies.

Riordan blasted those complaints in a blog post, directly titled "Leah Jeffries is Annabeth Chase," on his website.

"The response to the casting of Leah has been overwhelmingly positive and joyous, as it should be. Leah brings so much energy and enthusiasm to this role, so much of Annabeth’s strength," the author wrote. "She will be a role model for new generations of girls who will see in her the kind of hero they want to be."

He directed his attention to naysayers and shared a message directly with them: The bullying needs to stop.

"Whatever else you take from this post, we should be able to agree that bullying and harassing a child online is inexcusably wrong. As strong as Leah is, as much as we have discussed the potential for this kind of reaction and the intense pressure this role will bring, the negative comments she has received online are out of line."

Riordan added that he chose Jeffries and every other actor for their roles based on how well they are able to embody the characters' spirits.

"You refuse to believe me, the guy who wrote the books and created these characters, when I say that these actors are perfect for the roles because of the talent they bring and the way they used their auditions to expand, improve and electrify the lines they were given," he continued. "Once you see Leah as Annabeth, she will become exactly the way you imagine Annabeth, assuming you give her that chance, but you refuse to credit that this may be true."

"You are judging her appropriateness for this role solely and exclusively on how she looks. She is a Black girl playing someone who was described in the books as white," he added. "Friends, that is racism."

Riordan shared his message on social media alongside the hashtag #LeahIsOurAnnabeth. Check out his tweet below:

This is not the first time that casting for a fantasy series has evoked a racist response from fans. There was a stir in 2015 when Noma Dumezweni, a Black actress, was cast as Hermione Granger in the Broadway play Harry Potter and the Cursed Child.

Of course, the role was originally played by Emma Watson. At the time, J.K. Rowling, author of Harry Potter, condemned racist complaints about the casting in a similar manner to Riordan.

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