The network began looking for actors early this year for a reboot show inspired by JK Rowling‘s world-famous novels.
No cast members have been announced yet but 32,000 children sent in audition tapes for the lead roles of Harry, Hermione and Ron.
However, some big names are rumoured to be playing the roles of older characters.
British actor and Ted Lasso star Brett Goldstein is thought to be first choice to star as Rubeus Hagrid, who was originally played by Robbie Coltrane.
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No cast members have been announced yet but 32,000 children sent in audition tapes for the lead roles of Harry, Hermione and Ron
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However, some big names are rumoured to be playing the roles of older characters
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British actor and Ted Lasso star Brett Goldstein is thought to be first choice to star as Rubeus Hagrid, who was originally played by Robbie Coltrane
Harry Potter fans took to social media to express their disappointment and disapproval over the speculation.
‘What next? Weasleys are gonna be blonde, Malfoys ginger and Harry will wear eye contacts?’
‘Um Hagrid is supposed to be 8 feet tall and English.’
‘I don’t know if the world is ready for sexy Hagrid.’
Others branded the prospect ‘god awful’ and ‘a complete joke’.
Showrunner Francesca Gadiner previously explained that there will be some major differences between the Harry Potter films and the HBO series.
The characters will be the same age as in the books, meaning Professor Snape will be 31 and the Dursleys will also be played by younger actors.
Gangs Of London star Paapa Essiedu is rumoured to be portraying Severus Snape in the new series.
Gangs Of London star Paapa Essiedu is rumoured to be portraying Severus Snape, originally played by Alan Rickaman, in the new series
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Meanwhile, original Voldermort actor Ralph Fiennes has given his blessing for Cillian Murphy to play the notorious wizard of the dark arts, should he be offered it
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Star of BBC’s Wolf Hall: The Mirror And The Light, Mark Rylance is thought too be in the running to play Albus Dumbledore
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Sharon Horgan and Rachel Weisz are apparently being considered to take on the late Maggie Smith’s role as Hogwarts deputy headteacher Minerva McGonagall
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Bad Sisters star Sharon Horgan is allegedly in the running to play Professor McGonagall
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Oscar winner Rachel Weisz is also tipped to be considered for the part of Professor McGonagall
Meanwhile, original Voldermort actor Ralph Fiennes has given his blessing for Cillian Murphy to play the notorious wizard of the dark arts, should he be offered it.
Star of BBC’s Wolf Hall: The Mirror And The Light, Mark Rylance is thought too be in the running to play Albus Dumbledore.
Bad Sisters star Sharon Horgan and Oscar winner Rachel Weisz are apparently being considered to take on the late Maggie Smith’s role as Hogwarts deputy headteacher Minerva McGonagall.
In response to speculation over casting, HBO 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.’