"Game of Thrones" spin-off "House of the Dragon" released a poster and will be broadcast on August 21

The story focuses on the Targaryen family, involving their famous bloody civil war "A Dance with the Dragons", which goes back more than 200 years. Adapted from George R. R. Martin's book "Fire and Blood", Martin and Ryan Condal jointly developed it. The first season has 10 episodes, and the directors include Miguel Sapochnik, who directed many episodes of "Game of Thrones" such as "Battle of the Bastards" and "The Winds of Winter".

Trailer for "Dragon Family":

Matt Smith (Doctor Who) plays Prince Daemon Targaryen, the king's younger brother, heir to the throne, an unparalleled warrior and dragon rider with the blood of a true dragon, "but it is said that when every Targaryen family member was born, the gods threw a coin into the air."

Olivia Cooke (Ready Player One) plays Alicent Hightower, the daughter of "Hand of the King" Otto Hightower and the most beautiful woman in the Seven Kingdoms. She grew up in the Red Castle and was close to King Viserys and his circle of cronies. She is both gentle and elegant, and has a strong political acumen.

Emma Darcy ("Truth Seekers") plays Princess Rhaenyra Targaryen, the king's first child, a pure-blooded Valyrian who is also good at riding dragons. "Many people would say she is gifted, but not a man."

Paddy Considine (Peaky Blinders, The Outsiders) plays King Viserys Targaryen (Viserys I), who was chosen to inherit the throne of Jaehaerys Targaryen. He is a warm, kind and decent man who is determined to carry forward his grandfather's legacy, but a good man may not necessarily make a good king.

Steve Toussaint (Prince of Persia: The Sands of Time) plays Corlys Velaryon, the Sea Serpent, a great navigator.

Rhys Ifans (The Amazing Spider-Man) plays Knight Otto Highto.

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