John Lithgow is stepping into the role of Dumbledore for HBO's 'Harry Potter,' but he did have his reservations.

The Emmy-winning actor, hot off a SAG Award for "Conclave," said playing the Hogwarts headmaster would "define me for the last chapter of my life."

EXCLUSIVE: Following recent reports, actor John Lithgow now confirms that he will play Albus Dumbledore in HBO's upcoming Harry Potter TV show.

John Lithgow, the latest addition to the cast of HBO's Harry Potter remake, has commented on joining a series "full of great actors."

"It's going to define me for the last chapter of my life, I'm afraid." 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.

Harry Potter fans have voiced dismay at HBO 's rumoured first choice to play Severus Snape in the upcoming TV series, just days after a similar furore over an American actor being cast as Dumbledore.

As the HBO adaptation of Harry Potter goes further into production, more details are forthcoming on cast and crew members. John Lithgow has been drawing attention already for appearing to confirm his casting as Albus Dumbledore.

The wizarding world is making a comeback, and we're literally losing our minds over it. Nearly 25 years after Harry Potter first cast his spell on

As HBO puts together its cast for its high-profile series adaptation of the "Harry Potter" fantasy books, they have made a rather controversial casting decision regarding one of the main characters. According to a report from Deadline,

HBO’s upcoming adaptation of the Harry Potter series is one of the most anticipated (if not the most anticipated) events in the world of cinema (movies and TV included). The fans have been promised a lore-faithful,