HBO is forging ahead with its highly anticipated Harry Potter TV series, and it appears they've secured a key casting: John Lithgow is set to take on the iconic role of Professor Dumbledore.

According to reports, HBO has been on a quest to find the perfect Dumbledore, and it seems they've found their man. In a recent interview with ScreenRant, Lithgow confirmed his acceptance of the role, describing it as a defining moment in the "last chapter" of his life.

"Well, it came as a total surprise to me. I just got the phone call up at the Sundance Film Festival for yet another film, and it was not an easy decision because it’s going to define me for the last chapter of my life, I’m afraid," Lithgow shared.

He further expressed his excitement about the project, noting the involvement of some wonderful people in bringing Harry Potter back to life. "But I’m very excited. Some wonderful people are turning their attention back to Harry Potter. That’s why it’s been such a hard decision. I’ll be about 87 years old at the wrap party, but I’ve said yes."

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12 ImagesWhile this marks the first casting announcement for the upcoming Harry Potter TV series, it's worth noting that HBO and Warner Bros. have yet to officially confirm Lithgow's involvement.

HBO's ambitious plan is to adapt all of J.K. Rowling's beloved books into a television format, featuring an entirely new cast to portray beloved characters such as Harry Potter, Hermione Granger, Ron Weasley, and the rest of the Hogwarts community. J.K. Rowling herself will serve as an executive producer, alongside Neil Blair and Ruth Kenley-Letts.

Despite Lithgow's verbal confirmation, the absence of a complete cast suggests that the series is still some time away from entering full production.

John Lithgow, a seasoned actor known for his versatile roles in both film and television, is perhaps best recognized for his portrayal of Dick Solomon in the sitcom "3rd Rock from the Sun." He also garnered critical acclaim and an Emmy for his role as Winston Churchill in the first season of Netflix's "The Crown."