The official trailer for "House of the Dragon" is here.
The new HBO series is a "Game of Thrones" prequel based on George R.R. Martin's "Fire & Blood" series, which is set 200 years before the events of "Game of Thrones" and tells the story of House of Targaryen, the ancestors of Daenerys Targaryen (Emilia Clarke).
The trailer for "House of the Dragon" features stars Olivia Cooke as Alicent Hightower, "The Crown" actor Matt Smith as Prince Daemon Targaryen and Steve Toussaint as Lord Corlys Velaryon.
Other stars include Paddy Considine, Fabien Frankel, Eve Best, Sonoya Mizuno, Wil Johnson, John Mcmillan, Savannah Steyn and Theo Nate.
"House of the Dragon" is set to premiere on Aug. 21.
ABC News' Stephen Iervolino contributed to this report.