Rick Riordan, writer and author of the popular fantasy novel “Percy Jackson,” is speaking out against critics angered by the casting of Leah Jeffries. The actress, who is Black, is set to star as one of the leads in the upcoming adaptation set to release on Disney+.

In a lengthy blog post published earlier this week, Riordan condemned the racist remarks made toward the young star set to play Annabeth Chase in “Percy Jackson and the Olympians.”

(L) Rick Riordan and (R) Leah Jeffries. Photo by David Livingston/Getty Images, Monica Morgan/WireImage

“This post is specifically for those who have a problem with the casting of Leah Jeffries as Annabeth Chase,” Riordan wrote. “It’s a shame such posts need to be written, but they do…Leah brings so much energy and enthusiasm to this role, so much of Annabeth’s strength. She will be a role model for new generations of girls who will see in her the kind of hero they want to be.”

Riordan dared those with a “problem” with this casting to “take it up with me.” He added, “You have no one else to blame. Whatever else you take from this post, we should be able to agree that bullying and harassing a child online is inexcusably wrong.”

The New York Times bestselling author said that although he and Leah “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.” He added, “They need to stop. Now.”

After the announcement, fans of the mythological adventure called out the cast for not staying true to the book, like one Twitter user who said, “I really wanted them to do everything by the book…. She might be perfect and a great actress but Annabeth is supposed to be blonde hair with grey eyes like Athena.”

To comments like that, the author said, “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. Friends, that is racism.”

Riordan noted that he made “quite clear a year ago” that when he began his hunt for actors in the highly anticipated project, “we would be following Disney’s company policy on nondiscrimination” before providing what that entails:  We are committed to diverse, inclusive casting. For every role, please submit qualified performers without regard to disability, gender, race and ethnicity, age, color, national origin, sexual orientation, gender identity, or any other basis prohibited by law. 

The author noted, “We did that,” and “The casting process was long, intense, massive and exhaustive.”

Jeffries also received support from “Percy Jackson” alumni Alexandra Daddario, who formerly held the role of Chase in a previous adaptation. “Leah Jeffries is going to be an incredible Annabeth!!!” the actress wrote of her successor in a Twitter post earlier this week. 

Warm messages continued to pour in, including one from a Twitter user who commented, “A REMINDER THAT NO HATE FOR WALKER SCOBELL, LEAH SAVA JEFFRIES, AND ARYAN SIMHADRI ARE ALLOWED. THEY ARE CHILDREN GIVE THEM LOVE INSTEAD BC THEY’RE THE PERFECT CASTING FOR THE PERCY JACKSON TV SHOW.”