Harry Potter series 'lines up cast for Severus Snape and Professor McGonagall'

Essiedu's casting has been rumoured since December 2024 with no news actually being confirmed on whether the I May Destroy You alum will be officially joining the cast or not. As of 8th March, it's looking likely but HBO have declined to comment on the matter.

HBO did say in a statement: “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.”

What we do know is that the roles themselves are major for the Potter universe, with both Severus Snape and Professor McGonagall being previously played in the movies by late acting legends Alan Rickman and Dame Maggie Smith, respectively.

The series itself will be based on all seven books in the series and will "become a decade-long series produced with the same epic craft, love and care this global franchise is known for," according to a statement from Max.

Designed to run over the course of a decade, the series comes from writer and showrunner Francesca Gardiner and director Mark Mylod. When speaking at an event for Max back in December, Gardiner confirmed that the new series will stick to the "canonical" age of Snape, who will only be 31 in the show and much younger than he was in the films. Therefore, the casting selection of Essiedu is more than fitting.

While things are yet to be confirmed, both actors bring a wealth of experience to the table but tackling the world of Potter will undoubtedly be a major feat. Of course, McTeer is known for her roles in Ozark, Tumbleweeds, The Menu and more recently, KAOS.

Essiedu has also been at the helm of numerous TV shows including The Capture, Gangs of London, The Lazarus Project and has more recently been seen in Black Mirror's Demon 79.

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For both, it will also mark a return to HBO, with McTeer having starred in film Into The Storm as Winston Churchill's wife Clementine, while Essiedu starred in Michaela Coel's hit series I May Destroy You for the network.

As previously mentioned, Lithgow has now been confirmed as Hogwarts headmaster Dumbledore, with the actor telling Screen Rant: "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."

Lithgow also confirmed that he will be adopting an English accent for the role, 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."

The Harry Potter series will stream on Max.

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