How Will the Harry Potter Series Handle Its Young Stars’ Growth Spurts? HBO’s Casey Bloys Weighs In

There’s a specific kind of mischief that HBO’s Harry Potter series will need to manage as production gets underway, and that’s the offscreen aging of its young stars.

In September, the network launched a casting call for its TV adaptation of J.K. Rowling’s novels, seeking children who, by April 2025, will be 9 to 11 years old and can feasibly play kid wizards Harry Potter, Ron Weasley and Hermione Granger. But in recent years, it’s become quite common for cable and streaming series to put two (or even three) years between seasons; in the case of shows like Netflix’s Stranger Things, which is led by young actors, those extra-long hiatuses have led to obvious disparities between the stars’ real ages and the younger ones they’re playing on screen.

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“It is something we’re thinking about,” HBO chairman and CEO Casey Bloys told reporters at a recent press conference, when asked how the show will navigate its stars’ growth spurts over time. “One of the ideas we talked about was shooting the first season and the second season very close to each other time-wise, because 11 to 13 is a big jump in kids’ lives. You can get away with 13 to 15, something like that. So we’re going to have to think about scheduling and shooting so that they don’t grow too much between seasons. It is a consideration.”

Not much is currently known about the Harry Potter series’ production timeline, and no casting has been announced as of press time. When the show was formally ordered in April 2023, HBO — well, Max, at the time — made a 10-year commitment to the project, but it has yet to be clarified whether the show will span 10 seasons or simply be on the air for 10 total years, regardless of season count. (Harry Potter‘s previous eight film adaptations released, at most, two years apart between 2001 and 2011.)

And though Warner Bros. Discovery boss David Zaslav previously teased a 2026 debut for the series, Bloys’ current estimate is a bit less exact.

Harry Potter TV Series HBO
Harry Potter TV Series HBO

Harry Potter TV Series: Everything We Know

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“When we started the whole thing, we kind of laid out, ‘Oh, it could probably be ’27, something like that,'” he shared. “But don’t hold me to any of that, because we’re just getting started in the writing and casting process.”

The HBO exec is also unsure that new Harry Potter seasons can realistically drop every year once the show debuts.

“I think an annual schedule will be tough, but it depends on how much is written ahead of time,” he said.

Francesca Gardiner (His Dark Materials) was previously tapped to serve as writer, executive producer and showrunner of the Harry Potter series, while Mark Mylod (Succession, Game of Thrones) will direct multiple episodes and exec-produce. Rowling is also on board as an EP. (With reporting by Dave Nemetz)

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