- He is the first actor to confirm his involvement in the show
- Lithgow was previously seen in the likes of Shrek and The Crown
- Production begins later this year

We now know who the first confirmed member of the cast for the new Harry Potter TV show will be.
John Lithgow confirmed in an intervie with Screenrant that he will play Dumbledore in the forthcoming show. HBO hasn’t commented on his casting.
“It came as a total surprise to me,” Lithgow said. “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.”
The actor continued, “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.”
Lithgow’s casting marks an interesting deviation from the casting of the original series of films. When they were made, Rowling stipulated that she wanted the cast to exclusively be British. Given that Lithgow is American, this means we might see more international actors becoming a part of the franchise.
Who else is rumoured to be joining the cast?

Mark Rylance was previously rumoured to be taking on the role of Dumbledore. As we wait for more cast announcements, there remains plenty of speculation about who could be joining.
Read more: Harry Potter TV series to start filming next year
Paapa Essiedu is reportedly lined up to play Severus Snape. Other rumours include Ted Lasso star Brett Goldstein as Hogwarts gamekeeper Hagridand Bad Sisters’ Sharon Horgan as Minerva McGonagall.
As for the central trio of Harry, Hermione and Ron, a huge casting call went out. Children auditioning had to be between the ages of nine and eleven in April 2025 and residents of the UK or Ireland as of April 2025.
What else do we know about the Harry Potter TV show?

Production will begin at Warner Bros Studios Leavesden in Hertfordshire in summer 2025, the same space where the original Harry Potter movies were shot.
Read more: Everything we know about the Harry Potter TV show
Warner Bros. Discovery had eyed a release window of 2026. Shortly after this was revealed, HBO chairman and CEO Casey Bloys said it could be pushed to 2027.
Mark Mylod and Francesca Gardiner, who previously worked on Succession, are showurnners while author JK Rowling will be an executive producer.