Game of Thrones prequel's full main cast revealed

HBO has revealed more about its upcoming Game of Thrones prequel spinoff, including its full core cast and the first episode's director.

Eight rising stars have been cast in main roles, set to star alongside Naomi Watts, who was previously announced as a series lead.

What roles each new actor is playing is being kept under wraps, but a little more about the plot has also been teased.

"Only one thing is for sure: From the horrifying secrets of Westeros' history to the true origin of the White Walkers, the mysteries of the East to the Starks of legend - it's not the story we think we know," HBO says in a logline.

Meanwhile, SJ Clarkson has joined the prequel as pilot director and executive producer. She's directed episodes of Jessica Jones, Orange is the New Black and Succession.

Josh Whitehouse has also been previously announced as a major cast member.

More info on the newly announced actors are as follows:

Game of Thrones prequel star Georgie Henley's age and credits.
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Georgie Henley

British actor, 23, who has starred in three Narnia movies along with Access All Areas and The Sisterhood of Night.

Game of Thrones prequel star Toby Regbo's age and credits.
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Toby Regbo

British actor, 27, who played the young version of Dumbledore in Fantastic Beasts: The Crimes of Grindelwald. He's also starred in fantasy TV shows Reign and The Last Kingdom.

Game of Thrones prequel star Naomi Ackie's age and credits.
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Naomi Ackie

British actor, 27, who has a leading this year's Star Wars: Episode IX. She received accolades for her debut film role in 2017's Lady Macbeth.

Game of Thrones prequel star Denise Gough's age and credits.
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Denise Gough

Irish stage actor, 39, who won acclaim for roles in People, Places and Things and Angels In America. She also starred in the film Colette, playing transgender pioneer Marquise de Belbeuf.

Game of Thrones prequel star Sheila Atim's age and credits.
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Sheila Atim

British stage actress who won the 2018 Laurence Olivier Award for Best Supporting Actress in a Musical for her role as Marianne in Girl From The North Country. Age listed as "20 - 30s".

Game of Thrones prequel star Alex Sharp's age and credits.
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Alex Sharp

British actor, 29, best known for originating the role of Christopher Boone in the Broadway production of The Curious Incident of the Dog in the Night-Time. Also starred in 2017's How to Talk to Girls at Parties.

Game of Thrones prequel star Ivanno Jeremiah's age and credits.
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Ivanno Jeremiah

British actor, age unknown, who has starred in TV shows Humans and Black Mirror, along with computer game World of Warcraft: Battle for Azeroth.

Game of Thrones prequel star Jamie Campbell Bower's age and credits.
Photo credit: Getty

Jamie Campbell Bower

British actor and musician, 30, who starred in the Sweeny Todd movie, as well as the Twilight Saga and the Camelot TV show.

The Game of Thrones prequel spin-off will be broadcast after the final season of the main series, which premieres later this year.

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