HBO's Harry Potter on television, and the studio has recently been hard at work developing its cast. The process is still early on, but filming is intended to begin in August 2025, meaning the clock is ticking to fill out the roles of Hogwarts professors and the lead characters. We've already seen some major announcements.

Veteran actor John Lithgow was the first to the Harry Potter TV show cast, where he'll be playing Albus Dumbledore. As per Deadline, stars are currently closing in on deals for Severus Snape and Minerva McGonagall. The two actors being circled are Paapa Essiedu and Janet McTeer, both of whom have a number of interesting acting credits to their names. There's one detail of note with the casting ideas, particularly pertaining to the film adaptations' strategy.

The Harry Potter Show's Snape & McGonagall Plan Proves It's Still Prioritizing British Actors

The Show Is Sticking To The Movies' Main Rule

While the Harry Potter movies weren't always identical to the source material, they're generally praised for being outstanding adaptations. One of the ways in which the movies maintained authenticity to the text was by prioritizing British actors, with almost all of the cast being from the UK or Ireland. Except, of course, for characters intentionally from other countries like Fleur Delacour or Igor Karkaroff. Peter Dinklage is an American actor who's pulled off playing British in a period fantasy piece (Game of Thrones), but it generally doesn't work.

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There was some concern, primarily after John Lithgow's casting, that the TV series would be incorporating more actors from the US. However, the recent casting plan seems to suggest that HBO will pursue British talent. Though it's not the same production team, HBO is known for excellent casting on shows like Game of Thrones and House of the Dragon, while the ensembles are composed primarily of stars from the UK, which could be another promising sign. This cardinal rule helps not only with authenticity but also the story's cultural context.

The Remake's Dumbledore Might Be American, But It Hasn't Abandoned The Movies' Cardinal Rule

John Lithgow Is A Worthy Exception To The Rule

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Though John Lithgow is an American actor, we're letting him slide on this. John Lithgow has proven he can play British multiple times, having even won an Emmy for playing Winston Churchill. That's a major flex for an American. He also has a history of Shakespearean stage work dating back to his early days as an actor and is currently playing Roald Dahl for a play on the West End in London. He may be American, but the Harry Potter show's Dumbledore will be in capable hands.

Sources: Deadline

Harry Potter Updated 2026 TV Show Teaser Poster
Harry Potter
Showrunner
Francisca Gardiner
Directors
Mark Mylod
Writers
sca Gardiner
Franchise(s)
Harry Potter
  • Cast Placeholder Image
    Dominic McLaughlin
    Harry Potter
  • Headshot Of Janet McTeer
    Janet McTeer
    Minerva McGonagall
  • Headshot Of John Lithgow
    Albus Dumbledore
  • Headshot Of Nick Frost
    Nick Frost
    Hagrid