The “Game of Thrones” prequel pilot at HBO is taking shape.

Naomi Ackie, Denise Gough, Jamie Campbell Bower, Sheila Atim, Ivanno Jeremiah, Georgie Henley, Alex Sharp, and Toby Regbo have all joined the pilot in series regular roles. They join previously announced cast members Naomi Watts and Josh Whitehouse. As with all things “Game of Thrones,” the exact nature of each of their roles is being kept under wraps.

In addition, SJ Clarkson has signed on to direct the pilot in addition to serving as an executive producer. Clarkson was most recently selected to direct the next film in the rebooted “Star Trek” franchise. She also recently executive produced and directed the limited series “Collateral” for BBC and Netflix. Her other directing credits include: the Marvel-Netflix shows “The Defenders” and “Jessica Jones,” the Netflix series “Orange Is the New Black,” HBO’s “Vinyl” and “Succession,” and Showtime’s “Dexter.”

Ackie will star in the upcoming blockbuster “Star Wars: Episode IX” directed by J.J Abrams. She has also filmed a leading role in the film “The Corrupted,” a London crime thriller. She was recently seen in “Yardie,” the film that served as the directorial debut of Idris Elba. Her television credits include the U.K. shows “The Bisexual,” Cleaning Up,” and “Doctor Who.”

Gough recently appeared in Wash Westmoreland’s “Colette” alongside Keira Knightley and Dominic West. It was also recently announced that she would playing the lead role in “Monday.” Also starring Sebastian Stan, the film focuses on two self-destructive Americans living across Athens and the Greek Islands. She will next appear in Joe Cornish’s “The Kid Who Would Be King.” Her recent TV credits include the BBC2 series “Paula” and the Sky Atlantic/Showtime series “Guerrilla.”

Bower is a British actor and musician. He has appeared in films like Tim Burton’s “Sweeney Todd,” as well as the “Twilight” films and “The Mortal Instruments: City of Bones.” On the TV side, he appeared in “Will” for TNT, “Camelot” for Starz,” and in AMC’s remake of “The Prisoner.” He is the lead singer, guitarist, and founding member of the musical group Counterfeit.

Atim is known primarily for her stage work, having appeared in in award-winning theatre productions in the West End, The Royal Shakespeare Company, Donmar Warehouse, and The Old Vic. She won an Olivier Award for her performance as Marianne Laine in “Girl From the North Country.” She launched her TV career in 2018 as a series regular in the Hulu show “Harlots.”

Jeremiah will star in the upcoming film “The Flood” opposite “Game of Thrones” stars Lena Headey and Iain Glen. He also stars in the sci-fi series “Humans,” which airs on Channel 4 in the U.K. and AMC in the U.S. His other TV roles include “Doctor Who,” “Black Mirror,” “The Jury,” and “Injustice.”

Henley is best known for playing Lucy in the three “Chronicles of Narnia” films. Most recently, she filmed a role in the first season of the upcoming Starz series “The Spanish Princess.” She has also appeared in the independent films “Perfect Sisters,” “Sisterhood of Night,” and “Access All Areas.”

Sharp was cast as the lead in the stage adaptation of Mark Haddon’s best-selling novel “The Curious Incident of the Dog in the Night-Time” right out of Juliard. He recently starred opposite Elle Fanning and Nicole Kidman in John Cameron Mitchell’s “How to Talk to Girls” at Parties” and Marti Noxon’s “To the Bone,” starring alongside Keanu Reeves and Lilly Collins. He will also appear in the upcoming film “The Hustle.”

Regbo currently stars in the Netflix series “The Last Kingdom” and appeared in “Fantastic Beasts: The Crimes of Grindelwald.” His other TV credits include “Medici: Masters of Florence” and “Reign.” On the film side, he starred in projects like “uwantmetokillhim?” and “Someday This Pain Will Be Useful to You.”

Clarkson is repped by WME in the U.S. and Curtis Brown in the U.K. Ackie is repped by CAA, Hamilton Hodell in the U.K. and Cinetic Media and Peikoff Mahan in the U.S. Gough is repped by Independent Talent Group in the U.K. and UTA in the U.S. Bower is repped by Paradigm in the U.S. and Dalzell and Beresford in the U.K., Sloane, Offer, Weber, and Dern is his law firm and Vector is his music manager. Atim is repped by Middleweek Newtown Talent Management, Fourward, and Jackoway Tyerman. Jeremiah is repped by Scott Marshall Partners Ltd and Luber Roklin Entertainment. Henley is repped by ICM, Hamilton Hodell, Ltd and art2perform and Peikoff Mahan in the U.S. Sharp is repped by CAA and Elin Flack Management. Regbo is repped by Authentic Talent and Literary Management, Independent Talent Group, and Jackoway Tyerman.

Taking place thousands of years before the events of “Game of Thrones,” the new show chronicles the world’s descent from the golden Age of Heroes into its darkest hour. And 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.

Jane Goldman co-created the project with George R.R. Martin, whose “A Song of Ice and Fire” novel series serves as the basis for “Game of Thrones.” Goldman and Martin wrote the story, with Goldman writing the teleplay. She will also serve as showrunner. She and Martin will executive produce along with Clarkson, Daniel Zelman, James Farrell, Jim Danger Gray, and “Game of Thrones” executive producer Vince Gerardis. Chris Symes will co-executive produce.

(Pictured: S.J. Clarkson)

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