'Game of Thrones' Prequel 'House of the Dragon' Warns 'War Is Afoot' in Official Trailer

The anticipated series premieres Aug. 21 on HBO.

The Game of Thrones spinoff, House of the Dragon, has debuted its official trailer -- and it's a spectacle!

Based on George R.R. Martin's 2018 novel, Fire & Blood, the anticipated prequel is set 200 years before the events of the original series and tells the story of the House Targaryen. 

In the nearly three-minute trailer, released three days before its San Diego Comic-Con appearance Saturday, the question of who is the rightful heir to the throne becomes the catalyst for the tension and dramatics that soon unfold.

"I will not be made to choose between my brother and my daughter," King Viserys Targaryen (Paddy Considine) declares.

But some in the Targaryen clan are taking matters into their own hands, with the king's younger brother, Prince Daemon Targaryen (Matt Smith), anointing himself the successor.

But the king's daughter, Princess Rhaenyra Targaryen (Emma D'Arcy), has her sights set on being queen, even though that is "not the order of things." "When I am queen, I will create a new order," she says. 

"War is afoot." It most certainly is. Watch the trailer below.

Joining Considine and Smith are Olivia Cooke, Emma D'Arcy, Steve Toussaint, Eve Best, Fabien Frankel, Sonoya Mizuno and Rhys Ifans.

Milly Alcock, Bethany Antonia, Phoebe Campbell, Emily Carey, Harry Collett, Ryan Corr, Tom Glynn-Carney, Jefferson Hall, David Horovitch, Wil Johnson, John Macmillan, Graham McTavish, Ewan Mitchell, Theo Nate, Matthew Needham, Bill Paterson, Phia Saban, Gavin Spokes and Savannah Steyn also star in the series.

House of the Dragon premieres Sunday, Aug. 21 on HBO and will be available to stream on HBO Max.

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