Harry Potter cast rumours for new TV series

He called the role one which will "define me for the last chapter of my life" - showing he appreciates the importance with which fans view the character, who was previously played by Richard Harris and Michael Gambon.

Now, as big-name actors look to be in talks to play Severus Snape and Minerva McGonagall, all eyes will be on the rest of the cast for the series, which will have Francesca Gardiner (His Dark Materials) as its showrunner and Mark Mylod (Succession) as its producer and key director.

But who is currently expected to step into 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 February 2025, Conclave and The Crown star John Lithgow seemingly confirmed that he will play Albus Dumbledore in the series, in an interview with Screen Rant.

In the interview, Lithgow said: "It came as a total surprise to me. 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."

Meanwhile, Lithgow confirmed he would be adopting an English accent for the role in an interview with Collider saying: "[He's] certainly an Englishman. In fact, there’s a good deal of controversy that an American has been hired to play him. He’s such an icon. I’m half-English."

He continued: "I’ve just played Roald Dahl. I’ve played Winston Churchill. I’ll spend some time with a dialect coach, don’t worry about that.

"But no, I mean, Dumbledore couldn’t possibly be anything other than English. I just have to do my best. The wonderful thing is, I was welcomed by every English actor I worked with on The Crown. They had far more confidence in me and my Englishness than I did myself."

HBO has yet to officially confirm Lithgow's casting.

Lithgow's apparent confirmation came after a report in Deadline noted that he was in final negotiations to take on the role. Previous names reported to be in contention included Mark Rylance and Mark Strong.

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."

Essiedu's casting was further reported in March 2025, with the actor reportedly close to striking a deal to play Snape.

Who could play Minerva McGonagall?

There are numerous rumours about who could take on the role of Hogwarts deputy head Minerva McGonagall.

Two names which have previously come up as contenders are Bad Sisters creator and star Sharon Horgan, and The Mummy, Black Widow and Dead Ringers star Rachel Weisz.

However, more recently it has been reported by Deadline that KAOS and Ozark star Janet McTeer is in negotiations to play the role, which was previously played by the late Dame Maggie Smith.

Obviously, at this time none of these names are locked in, meaning a brand new contender could also emerge to take the role.

Who could play Rubeus Hagrid?

Ted Lasso and Shrinking star Brett Goldstein has been rumoured for the role of Rubeus Hagrid, as previously played by Robbie Coltrane.

Goldstein has been best-known for his comedy work, but dipped his toe into big franchise fare when playing Hercules during the post-credits scene of Thor: Love and Thunder. We'll have to wait and see whether he takes on another iconic character and plays the Hogwarts gamekeeper.

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.

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