J.K. Rowling is calling out racism for what it is.
The Harry Potter and the Cursed Child author re-addressed critics of the casting of Noma Dumezweni, a black woman, as Hermione Granger in the upcoming play set for London's West End.
"I had a bunch of racists telling me that because Hermione 'turned white' -– that is, lost color from her face after a shock –- that she must be a white woman, which I have a great deal of difficulty with," the 50-year-old novelist told U.K.'s The Guardian. "But I decided not to get too agitated about it and simply state quite firmly that Hermione can be a black woman with my absolute blessing and enthusiasm."
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Rowling expressed her support of casting the Olivier Award-winning actress in the part -- which picks up nearly 20 years after the Harry Potter series and features grown-up Ron and Hermione and their daughter, Rose -- in December, tweeting, "Canon: brown eyes, frizzy hair and very clever. White skin was never specified. Rowling loves black Hermione."
Emma Watson, who plays Hermione in the movies, also tweeted out support in January, writing, "Can't wait to see Noma Dumezweni as Hermione on stage this year."
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Dumezweni replied to Watson, tweeting, "Thank You Miss Watson! Much appreciated. I look forward to experiencing #Hermione too. Blessings Abound to you."
Also, ahead of the play’s big debut, Rowling posted a plea for fans who see the performances in London to "keep the secrets," and not spoil the surprises for everyone else who’s waiting for the production to come to their area.
Harry Potter and the Cursed Child begins previews on Tuesday, and is set to premiere in London on July 30.
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Meanwhile, fans of Rowling know how vocal she is against shamers on the internet.
Watch the video below to see the author's response to an online troll who went after Serena Williams.