Matt Smith as Daemon Targaryen

Matt Smith is best known for his roles in Doctor Who and The Crown, and his take on the dark prince Daemon already feels iconic.

Milly Alcock as young Rhaenyra Targaryen

Milly Alcock is an Australian actor who has appeared primarily in Australian productions before now, including Janet King, A Place to Call Home, Pine Gap, and Upright. Her portrayal of the young Rhaenyra Targaryen is one of the highlights of House of the Dragon.

Emma D'Arcy as adult Rhaenyra Targaryen

Emma D'Arcy will play the aged-up version of Rhaenyra after the show does a time jump. Before House of the Dragon, Emma appeared in shows like Wanderlust, Truth Seekers, and Hanna.

Emily Carey as young Alicent Hightower

Emily Carey is the picture of innocence as young Alicent. This is perhaps Emily's biggest role to date; she previously appeared in series like Get Even and Casualty.

Olivia Cooke as adult Alicent Hightower

Taking over the role of Alicent after the time jump is Olivia Cooke, whom you might know from Bates Motel, Vanity Fair, and Me and Earl and the Dying Girl.

Paddy Considine as Viserys Targaryen

Paddy Considine looks quite different with his platinum Targaryen wig. He has extensive screen credits pre–House of the Dragon, including roles in Peaky Blinders, The Third Day, and The Outsider

Sian Brooke as Aemma Arryn

Sian Brooke's time onscreen as Aemma Arryn was short but significant. She has also appeared in shows like Good Omens and Sherlock.

Rhys Ifans as Otto Hightower

Rhys Ifans's eclectic career includes roles in Notting Hill, Harry Potter and the Deathly Hallows, and Spider-Man: No Way Home, and his take on Otto Hightower is delightfully calculating.

Sonoya Mizuno as Mysaria

Sonoya Mizuno is intriguing as the mysterious Mysaria. You might remember the actor from Maniac or Crazy Rich Asians.

Steve Toussaint as Corlys Velaryon

After the first episode of House of the Dragon, Steve Touissant quickly emerged as a fan favorite in the role of Corlys Velaryon. His prior credits include Pine Gap, Doctor Who, and Prince of Persia: The Sands of Time

Eve Best as Rhaenys Velaryon

Eve Best forms the other part of Westeros's current power couple as Rhaenys Velaryon. Previously she's appeared in Nurse Jackie and The King's Speech.

Fabien Frankel as Criston Cole

The handsome Fabien Frankel plays the handsome Criston Cole. You might have seen him in The Serpent before this.

Graham McTavish as Harrold Westerling

Graham McTavish has been in The Hobbit and Outlander and is now bringing his Scottish accent to Harrold Westerling of the Kingsguard in House of the Dragon.