It was recently announced following his casting as spymaster Dijkstra in the second season of Netflix smash The Witcher, Graham will also be playing Ser Harrold Westerling in House of Dragons.
He is also set to be joined by Outlander co-star and fellow Scot Bill Paterson, who will be playing Master of Coin, Lord Lyman Beesbury.
The pair will join five others announced by HBO for the highly-anticipated drama series which is filming now and is set to air in 2022.
Graham has already been snapped on set mounted on a white horse in his Kingsguard uniform.
The Scots star is beginning to make a name for himself starring in hugely popular film and tv shows based on some of the world’s favourite fantasy novels.
Best known as war chief Dougal MacKenzie in Outlander, he has also starred as the dwarf Dwalin in the film adaptation of JRR Tolkien’s classic story, The Hobbit.
Bill will also soon be on set, the Veteran Scots actor, who played lawyer Ned Gowan in Outlander, is joining the glittering cast which also includes the likes of Paddy Considine, Olivia Cooke, Emma D’Arcy, Matt Smith, Steve Toussaint, and Rhys Ifans.
The highly anticipated series will be set over a century before the current Game of Thrones and will focus on the Targaryen Family and the civil war they indulge in which becomes known as the Dance of the Dragons.
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