J.K. Rowling has blasted critics of Noma Dumezweni, insisting she was the perfect actress to play a grown-up Hermione in a new Harry Potter play.
The thought of a black actress as Potter's pal has not been welcomed by all fans, prompting Rowling to call those opposed to the casting "a bunch of racists".
The writer told The Observer newspaper she had "a great deal of difficulty" with the idea the character, portrayed by former child star Emma Watson in the Potter films, must be "a white woman."
Rowling went on to call Noma the "best actress for the job", telling the publication, "What can you say? That's the way the world is", adding, "I simply state quite firmly that Hermione can be a black woman with my absolute blessing and enthusiasm."
The first official cast photos of Dumezweni as Hermione Granger, Paul Thornley as Ron Weasley and Cherrelle Skeete as the fictitious couple's daughter Rose Granger-Weasley in Harry Potter and the Cursed Child were released earlier this week.
When Dumezweni's casting was announced last year, Rowling said Hermione's ethnicity was "never specified" and that she "loved" the idea of a non-white actress playing her.
The production, which is the eighth story in the Potter series and the first one to be presented on stage, opens for previews at London's Palace Theatre on Tuesday, and Rowling is hopeful critics and theater fans who catch an early show will keep details of the plot to themselves - and not spoil the fun for other Potter devotees.
The play, which tackles the ongoing story of the Harry Potter kids as adults and parents, officially opens on July 30.
The author added, "I hope we get there without any major spoilers, purely because people will have an amazing experience if they don't know what's coming."