Harry Potter cast rumours for new TV series

Francesca Gardiner (His Dark Materials) has been recruited as showrunner for the ambitious project, while Succession and The Menu director Mark Mylod will produce and helm several episodes.

But beyond those behind-the-camera creatives, there are still a lot of questions over who exactly will be involved in this latest iteration of the Wizarding World.

If you're curious to know the current leading rumours, you've come to the right place! Here's everything we know so far about what the cast of the Harry Potter TV series might look like.

Harry Potter series cast rumours explained

Who could play Professor Dumbledore?

In November 2024, Variety reported that Academy Award winner Mark Rylance was being considered for the important role of Albus Dumbledore in the Harry Potter TV series.

The actor, who is currently earning high praise for his performance as Thomas Cromwell in Wolf Hall: The Mirror and The Light, is also known for Stephen Spielberg collaborations Bridge of Spies, The BFG and Ready Player One.

He would be the fifth actor to portray the role in live-action, following Richard Harris, Michael Gambon, Toby Regbo (in Deathly Hallows flashbacks) and Jude Law (in the Fantastic Beasts films).

Rylance's involvement in the Harry Potter TV series remains unconfirmed, so take it with a pinch of salt for now.

Who could play Severus Snape?

In December 2024, The Hollywood Reporter claimed that Paapa Essiedu was in contention for the role of Professor Severus Snape in the Harry Potter TV series.

The actor began his career in theatre, before taking screen roles in I May Destroy You, Gangs of London and The Lazarus Project, while he also makes a guest appearance in Netflix's brand new spy thriller Black Doves.

Formerly played by the late Alan Rickman, Essiedu's casting would mark a major milestone for the Harry Potter franchise, which has been criticised in the past for lacking diversity.

Once again, though, it's important to note that this casting is not yet confirmed, with HBO releasing a statement to clarify that it won't be formally acknowledging any potential cast members until their contracts are signed.

The broadcaster said (via THR): "We appreciate that such a high-profile series will draw a lot of rumour and speculation. As we make our way through pre-production, we will only confirm details as we finalise deals."

Who could play Lord Voldemort?

A recent rumour attaching Oppenheimer star Cillian Murphy to the role of Lord Voldemort has recently been debunked.

The casting of the sinister villain will be a crucial component to the success of the Harry Potter streaming show, with their rivalry spanning across each of JK Rowling's original novels.

Fresh off his Academy Award win and capable of intense, dark performances, Murphy would have been a choice few could have protested, but it appears that talk of his involvement is not to be taken seriously.

In its recent update, sources close to the project told The Hollywood Reporter that rumours surrounding the Peaky Blinders actor were "not correct", which may come as a disappointment to fans – including former Voldemort star Ralph Fiennes.

During an appearance on Watch What Happens Live, the actor said: "Cillian is a fantastic actor. I actually think that's a wonderful, wonderful suggestion. I would be all in favour of Cillian." Oh well!

Who could play Harry, Ron and Hermione?

The central roles of Harry, Ron and Hermione will most likely go to unknown child actors, with a recent casting call seeking kids who will be aged between 9-11 in April 2025, when the show is scheduled to start shooting.

It's possible that the producers will opt to add some diversity here too, with Hermione previously being played by South African-British actor Noma Dumezweni (The Watcher) in stage show Harry Potter and the Cursed Child.

Recently, the Disney Plus adaptation of fellow young adult fantasy novels Percy Jackson and the Olympians also opted to diversify its leading roles by casting Leah Jeffries as Annabeth Chase.

The then-14-year-old actor faced racist trolling when the show came out, with Percy Jackson author and show producer Rick Riordan being one of many who came to her defence.

He wrote: "As strong as Leah is, as much as we have discussed the potential for this kind of reaction and the intense pressure this role will bring, the negative comments she has received online are out of line. They need to stop. Now.

"You are judging her appropriateness for this role solely and exclusively on how she looks. She is a Black girl playing someone who was described in the books as white. Friends, that is racism."

Harry Potter is coming to HBO and Max in 2026.

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