“It’s going to define me for the last chapter of my life, I’m afraid.”

John Lithgow; Michael Gambon as Dumbledore in ‘Harry Potter and the Order of the Phoenix’. Photo: Jamie McCarthy/Getty; Murray Close/Warner Bros.

John Lithgow is heading to Hogwarts.

The 3rd Rock From the Sun star confirmed recent rumors that he’ll be playing Professor Albus Dumbledore on HBO’s forthcoming Harry Potter TV series in an interview with Screenrant published Tuesday. “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 is the first actor to confirm their involvement in the series, and no official casting has been announced at this point.

Representatives for Lithgow and HBO didn’t immediately respond to Entertainment Weekly‘s requests for comment.

Lithgow is 79, and the Harry Potter series is expected to premiere in 2026 and adapt one of J.K. Rowling’s seven books per season. That means we’ll receive about one season per year if all goes according to plan, and Lithgow will wrap in 2033, when he’s 87.

Though Lithgow is American, he’s no stranger to playing British (and English-accented) characters. Some of his most recognizable performances include his turn as Winston Churchill on The Crown and voicing Lord Farquaad in the original Shrek.

John Lithgow at the 2025 Screen Actors Guild Awards.Kevin Mazur/Getty

That said, Lithgow’s casting could signify a key creative distinction between the upcoming HBO Potter series and the prior Warner Bros. film franchise. The movies opted to exclusively cast British actors as its witches and wizards, following an agreement between Rowling and Chris Columbus, who directed the first two installments. (One of the only exceptions was Columbus’ daughter, Eleanor, who played Susan Bones and ultimately never spoke on screen.) Lithgow’s casting suggests that more Americans and international actors might be a part of the new series’ ensemble.

Lithgow is a prolific and decorated actor, with more than 130 screen credits to date and dozens of stage performances to boot. He has two Oscar nominations under his belt, for his supporting roles in The World According to Garp and Terms of Endearment, and has six Emmys to his name, for his work on 3rd Rock from the Sun, Dexter, The Crown, and Amazing Stories. In recent years, he’s played key supporting roles in films like Conclave, Killers of the Flower Moon, Bombshell, and Pet Sematary.

Dumbledore was originally played by Richard Harris in the first two Potter films. Michael Gambon took over the role following Harris’ death in 2002, and Jude Law played a young version of the character in two Fantastic Beasts prequel films.

Francesca Gardiner (Succession, His Dark Materials, Killing Eve) is serving as showrunner, writer, and executive producer of the upcoming series, which has been described as a “faithful adaptation” of Rowling’s seven-book series. Mark Mylod (Succession, The Last of Us, Game of Thrones) will direct multiple episodes and executive-produce. Rowling is also executive-producing the series, which has stirred significant controversy due to her persistent transphobic comments.