'Percy Jackson' author Rick Riordan has defended Leah Sava Jeffries from "racist" online trolls.
The writer has addressed backlash over Jeffries being cast as Annabeth Chase - who was played by Alexandra Daddario in the 2010 and 2013 movies - in the upcoming Disney+ series, with the young actress being subject to vile abuse because she doesn't match the character's physical description in the book.
On his website, Riordan wrote: "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."
He also pointed to his own involvement in the casting, and called out critics for "bullying and harassing a child online".
He added: "If you have a problem with this casting, however, take it up with me. 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.
"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. They need to stop. Now.”
While noting that the response has been "overwhelming positive and joyous", he wanted to address "those who have a problem with the casting".
He noted he supported Disney's policy of blind casting and nondiscriminiation, and insisted the focus was on "the personalities of these characters".
He said: "I have been clear, as the author, that I was looking for the best actors to inhabit and bring to life the personalities of these characters, and that physical appearance was secondary for me.
“We did that. We took a year to do this process thoroughly and find the best of the best. This trio is the best. Leah Jeffries is Annabeth Chase.”
Riordan insisted anyone still complaining about the decision are not only dismissing the star's talent, but also his own integrity - and that they have misunderstood his books.
He continued: “If you don’t get that, if you’re still upset about the casting of this marvelous trio, then it doesn’t matter how many times you have read the books. You didn’t learn anything from them.”