Northern Ireland's own Conleth Hill, Ian McElhinney and Derek Halligan will join the cast of fantasy epic Game of Thrones, a production based on George R.R. Martin's best-selling novels.
Mark Huffam, also from Northern Ireland, will be producing the series in which hundreds of extras and crew will be employed.
The announcement follows confirmation that Coleraine actress Michelle Fairley has landed a lead role opposite Sean Bean and that Armagh man Brian Kirk has been lined up to direct two episodes of the 10-part series.
The US broadcaster HBO begins work in the city next week on the programme, which is expected to be one of the largest television series to be shot in Europe.
Political leaders at the Northern Ireland Assembly played their part in wooing US movie-makers to use locations in the region, but now local acting talent are set to perform alongside stars such as Sean Bean.
"We are delighted that HBO has signed up some of our best on-screen and off-screen talent for Game Of Thrones," said chief executive of Northern Ireland Screen Richard Williams.
"We have always sought to nurture local talent and support our indigenous film-makers. Game of Thrones will provide a great deal of experience for many local cast and crew.
"The decision by HBO to base the series here further cements our reputation as a leading centre for film and television production and it is estimated that £20 million will be delivered into the local economy."
Game Of Thrones is a new original HBO series based on the famous fantasy novels. Principal photography for the series begins next Monday in Belfast.
Northern Ireland Screen recounted the storyline of the epic novels: "In a world where summers span decades and winters can last a lifetime, the Westeros crown comes with a price.
"Betrayal, lust, intrigue and supernatural forces shake the four corners of the Kingdom, from the scheming south and the savage eastern lands, to the frozen north and the ancient Wall that protects the realm from the darkness beyond.
"Kings and queens, knights and renegades, liars and noble men vie for power in the bloody struggle for the Iron Throne."
Michelle Fairley (who starred in Best: His Mother's Son) will play Catelyn Stark, wife of Eddard Stark who is played by Sean Bean (Red Riding, Sharpe).
Conleth Hill (Perrier's Bounty) takes on the role of Varys, the calculating spymaster for the king of Westeros. Ian McElhinney has been cast as Ser Barristan Selmy, known to fans as Barristan the Bold and Derek Halligan (Fifty Dead Men Walking) will play Alliser Thorne.
The cast-list also includes Mark Addy (Robin Hood, Red Riding), Alfie Allen (Atonement), Aidan Gillen (The Wire, Queer As Folk), Peter Dinklage (Elf, The Station Agent), Nikolaj Coster-Waldau (Kingdom Of Heaven, Black Hawk Down), Lena Headey (300, The Brothers Grimm) and Jerome Flynn (Soldier, Soldier).
Brian Kirk (Dexter, Middletown) will share the director's chair with HBO regulars Daniel Minahan (True Blood, Six Feet Under) and Alan Taylor (Mad Men, Lost, The Sopranos). Other directors will be announced as they are confirmed.
Game Of Thrones has received funding from Northern Ireland Screen supported by Invest NI and part-funded by the European Regional Development Fund.
It will shoot in the Paint Hall studio, Belfast, as well as various locations in Northern Ireland.
The writers of the series are David Benioff and D.B. Weiss, who will pen seven episodes, and Bryan Cogman, Jane Espenson and George R.R. Martin, who will write one episode each.