Harry Potter TV series: Release date speculation and cast news

Lithgow's involvement may be a surprise to some, given that others such as Mark Rylance (Wolf Hall) and Mark Strong (The Penguin) have previously been rumoured. Lithgow is also, notably, an American, but has proved himself adept at playing Brits in previous roles, including in The Crown, where he played Winston Churchill.

News of his casting comes as the rumour mill surrounding potential stars heats up, just months ahead of cameras rolling on the first season, which is expected to start shooting this summer.

The ambitious show, headed to HBO and Max in the US, will be an entire retelling of the original Harry Potter saga.

While we await further news on the cast front, the show did recently make one concrete hiring – costume designer Holly Waddington, who won an Oscar for her work on Poor Things.

But what else do we know about the Harry Potter TV series so far? Read on to find out more.

Harry Potter TV series release date speculation

The new Harry Potter TV series is now expected to arrive in 2027, following a slight delay to the original timeline.

The project had initially been pegged for a premiere in late 2026, but in November of this year, HBO boss Casey Bloys said that it was looking unlikely that they would meet that target, instead pushing the series into the following year (via THR).

In December, he said that the plan is to start shooting the series in mid-summer 2025.

The delay isn't necessarily anything to worry about, with Bloys telling Deadline in September: "Writers have started. [Director] Mark Mylod has started.

"The team, they're hiring department heads, casting, and we're off... I feel very, very happy and excited about what they've got going."

He added that the broadcaster hopes to produce subsequent seasons at a faster rate than typical visual effects-heavy shows, citing how quickly children can age on screen.

"From 11 to 13 is a big jump in kids lives," he said. "We are going to think about scheduling, so they don’t grow too much between seasons. Annual [release] will be tough, but it depends on how much is written at a time."

The executive also confirmed that author JK Rowling is involved in the project, amid ongoing controversy online, which has turned some fans away from the beloved Wizarding World.

The author was absent from the 20-year anniversary special of the Harry Potter movies, while there were also boycotts of the Hogwarts Legacy game by some.

In response to these concerns, an HBO spokesperson said (via Variety): "We are proud to once again tell the story of Harry Potter – the heartwarming books that speak to power of friendship, resolve and acceptance.

"JK Rowling has a right to express her personal views. We will remain focused on the development of the new series, which will only benefit from her involvement."

Harry Potter TV series cast rumours: Who could star?

There is just one seemingly-confirmed cast member in the Harry Potter TV series so far - John Lithgow.

Lithgow is set to play Albus Dumbledore, with the Conclave and The Crown star having confirmed as much when speaking with Screen Rant. HBO has yet to officially announce the casting.

Lithgow said of taking on the role: "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."

An HBO spokesperson said: "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."

It had previously been reported by Variety that Wolf Hall star Mark Rylance was in line for the role, but that has seemingly changed since November 2024.

When it comes to other rumoured castings, in December 2024, The Hollywood Reporter claimed that I May Destroy You and The Lazarus Project alum Paapa Essiedu was in negotiations to play Professor Severus Snape – one of the saga's most complex figures.

Following these reports, the rumour mill went into overdrive, with Sharon Horgan and Rachel Weisz reportedly being in the running to play Minerva McGonagall, and Brett Goldstein reportedly being linked to the role of Rubeus Hagrid.

Elsewhere, there is currently an open casting call looking for three kids to play the central characters of Harry Potter, Ron Weasley and Hermione Granger, with Warner boss Channing Dungey admitting it would be "tricky" to allocate the roles (via Variety).

Hero Talent Group founder Nicole Tasker explained, in an interview with The Times, how the process of narrowing down the candidates would work.

She said: "The casting team will do open calls on social media, go to local drama groups and contact all the child agencies. It used to just be the big drama schools, but everything is more open now."

Those hoping for returns from the film franchise's stars, such as Daniel Radcliffe, Emma Watson or Rupert Grint, are out of luck – it's not looking likely.

Chatting to ComicBook.com, Radcliffe quashed any speculation about him making an appearance.

He said: "My understanding is that they’re trying to very much start fresh, and I'm sure whoever is making them will want to make their own mark on it and probably not want to have to figure out how to get old Harry to cameo in this somewhere."

He continued: "So I'm definitely not seeking it out in any way… but I do wish them, obviously, all the luck in the world, and I'm very excited to have that torch passed. But I don't think it needs me to physically pass it."

Argus Filch star David Bradley told RadioTimes.com: "I think it’ll be very interesting to see what they will do with the extra time they’ll have to film more of the books than we could.

"The Goblet of Fire and the last two, they were quite chunky – how do you condense those into a two and a half hour film?

"Of course, you’ve got to sacrifice quite a lot of plot and characters. I’m assuming the reason they’re doing it is they’ll be able to include more of the story because they’ll have more screen time - a lot more than the films had. I’ll be interested. I haven’t had the call yet!"

Asked whether it felt strange to see a new adaptation in the works, Jason Isaacs, who played Lucius Malfoy, mused: "It’s no weirder for me than for everybody else who’s seen the films. I happen to be in the films too."

He continued: "They make a new Spider-Man every 15 minutes. You know, there was a ton of stuff in the books that we left out. Yeah, it's an odd feeling, but it’s no odder for me than it is anyone else. I can’t wait to see them and see what they do."

Behind the camera, we know that His Dark Materials writer Francesca Gardiner will serve as showrunner, while Succession director Mark Mylod is attached to produce and film some episodes.

Meanwhile, JK Rowling will executive produce the series, alongside Neil Blair and Ruth Kenley-Letts.

"Max’s commitment to preserving the integrity of my books is important to me, and I’m looking forward to being part of this new adaptation which will allow for a degree of depth and detail only afforded by a long form television series," said Rowling.

What is the Harry Potter TV series about?

The series will be based on all seven books in the series, published between 1997 and 2007.

A statement from the newly branded Max explained: "The stories from each of Rowling’s Harry Potter books will become a decade-long series produced with the same epic craft, love and care this global franchise is known for.

"The series will feature a new cast to lead a new generation of fandom, full of the fantastic detail, much loved characters and dramatic locations that Harry Potter fans have loved for over 25 years."

It continued: "Each season will be authentic to the original books and bring Harry Potter and these incredible adventures to new audiences around the world, while the original, classic and beloved films will remain at the core of the franchise and available to watch globally."

The Harry Potter series will stream on Max.

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