Published 13:36 6 Apr 2026 GMT+1

Harry Potter actor John Lithgow reveals ‘extremely difficult thing’ about joining reboot

The actor opened up about it all in a new documentary that looks into the highly anticipated reboot ahead of its release later this year

Niamh Shackleton

Featured Image Credit: Bruce Glikas/WireImage

Topics: Harry Potter, HBO, News, Entertainment, Celebrity, Film and TV

Niamh Shackleton

Niamh Shackleton is an experienced journalist for UNILAD, specialising in topics including mental health and showbiz, as well as anything Henry Cavill and cat related. She has previously worked for OK! Magazine, Caters and Kennedy.

@niamhshackleton

Emmy Award-winning actor John Lithgow has reflected on joining the cast of the Harry Potter reboot at the age of 80.

It was confirmed last year that Lithgow would be taking on the role of Albus Dumbledore for the TV series, following in the footsteps of Michael Gambon and Richard Harris who played the Hogwarts headmaster in the film franchise.

Harris portrayed Dumbledore for the first two films before his passing in October 2022. Gambon was then hired to replace Harris for the third film, Harry Potter and the Prisoner of Azkaban, and kept the role until the films came to an end in 2011.

Now, 15 years later and fans of the wizarding world are getting a Harry Potter reboot in the form of a TV series, which will premier on HBO on Christmas Day, 2026.

John Lithgow is playing Albus Dumbledore in the Harry Potter reboot (HBO)

In anticipation for the series' release later this year, a new documentary titled Finding Harry: The Craft Behind the Magic has been released, which looks in detail at the making of the reboot.

80-year-old Lithgow features in the doc and reflects on him being cast as the fan favorite character of Dumbledore. While it's an undeniably wonderful achievement, it comes with a tinge of sadness for Lithgow...

"I knew that while I did the first season of Harry Potter, I would be turning 80 years old," he explains. "That meant that I would age to about 88 before it was all over."

Lithgow goes on: "This is an extremely difficult thing to contemplate. They're gonna grow up in this. And I'm gonna grow older with them."

The actor has made similar sentiments previously, stating that series will 'define me for the last chapter of my life'. With this in mind, Lithgow said accepting the role of Dumbledore wasn't 'an easy decision'.

Lithgow will be nearing 90 years old when the TV series wraps (Karwai Tang/WireImage)

"Well, it came as a total surprise to me," he told ScreenRant last year. "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. 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."

The Dexter actor was the first confirmed member of the reboot's cast. Since then, the three main characters – Harry Potter, Ron Weasley, and Hermione Granger – have been announced.

Young newcomers Dominic McLaughlin (Potter), Alastair Stout (Weasley), and Arabella Stanton (Granger) will star as the lead roles. Other members of the cast include Nick Frost, Paapa Essiedu, and Janet McTeer.