Unlike other book-to-film adaptations such as The Hunger Games taking the prequel route with new releases, the upcoming series "will be a faithful adaptation of the beloved Harry Potter book series," per an official press release from Warner Bros. Discovery.

It seems John Lithgow spilled the (Bertie Bott's Every Flavor) beans about his involvement in HBO's in-the-works 'Harry Potter' series. 'A total surprise to me,' he says.

John Lithgow has played everything from Don Quixote in Man of La Mancha to an extraterrestrial patriarch in 3rd Rock from the Sun. Next he will be the powerful, wise, and compassionate professor Dumbledore in HBO’s Harry Potter TV show. He confirmed the casting in a recent interview, saying it will “define me for the last chapter of my life.”

With the Harry Potter TV series starting filming in the summer of 2025, has the highly-anticipated show been cast yet? Here's what we know so far about who will play Harry, Ron, Hermione, Dumbledore and Snape.

John Lithgow being cast as Dumbledore in the upcoming "Harry Potter" series is more significant than you might think

When asked about the offer to play Dumbledore, Lithgow described the decision as "not easy," recognizing it could define the final phase of his illustrious career.

In an interview with ScreenRant, American actor John Lithgow confirmed that he will portray Dumbledore in the new Harry Potter series currently in production by HBO.