Game Of Thrones' House Of The Dragon Spinoff Adds A Doctor Who Star And More

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(Image credit: HBO)

The first Game of Thrones spinoff to score a series order is taking big steps forward before production begins in 2021, with three new cast members officially joining House of the Dragon. The show is set more than a hundred years before the events of Game of Thrones, so House of the Dragon can be packed full of Targaryens. Now, two more Targaryens have been cast, along with one more character, and a familiar face to Doctor Who fans is on board.

Three more characters have been cast for the adaptation of George R.R. Martin's Fire & Blood fictional history book, and they paint the picture of a bloody and intense series. Deadline reports that Matt Smith, best known for playing the Eleventh Doctor on Doctor Who before tackling the role of Prince Philip in the early seasons of The Crown, will be playing a different kind of royalty as Prince Daemon Targaryen.

Also cast have been the roles of Princess Rhaenyra Targaryen and Alicent Hightower. Rhaenyra will be played by Hanna and Truth Seekers alum Emma D'Arcy, and Alicent Hightower will be played by Olivia Cooke of Ready Player One and Bates Motel fame. Matt Smith, D'Arcy, and Cooke join Paddy Considine, whose casting as King Viserys Targaryen was announced back in October. Danny Sapani of Penny Dreadful is reportedly in talks to play another character from Fire & Blood: Lord Corlys Valaryon, known as the Sea Snake.

Now that House of the Dragon is slated to include King Viserys Targaryen (who should be very different from the Viserys that Game of Thrones likely remember), Princess Rhaenyra Targaryen, Prince Daemon Targaryen, the Sea Snake, and Alicent Hightower, I think it's safe to say that the show is going to tackle the Dance of the Dragons chapter of Targaryen history that more or less sowed the seeds of the dynasty's eventual destruction.

In the show, Matt Smith's Daemon is the younger brother to King Viserys and heir to the throne as a skilled warrior and dragonrider, whose dragon was seemingly revealed in the first look at House of the Dragon. That's not to say that he won't have a touch of the Targaryen madness that Game of Thrones revealed to have consumed Aerys, Viserys, and eventually Daenerys down the line. (And arguably Rhaegar.)

Emma D'Arcy's Princess Rhaenyra is a pure Valyrian dragonrider and firstborn child of King Viserys who is unfortunately at one big disadvantage in the typical line of succession: she's a woman. Olivia Cooke's Alicent Hightower is the daughter of Otto Hightower, who serves as Viserys' Hand of the King.

Known for her beauty, grace, and keen eye for politics, she was raised close to Viserys in the Red Keep. It hasn't been confirmed just yet if the show picks up with Alicent already married to Viserys, which would explain why there is no mention of their son, but a lot depends on how closely the show follows the Fire & Blood book.

For more on the twisted Targaryen family tree after generations of incest from the pages of Fire & Blood, here's a slightly spoilery summary. These characters become key players in the Dance of the Dragons, as told by George R.R. Martin's Fire & Blood. The Dance of the Dragons was a Targaryen civil war over the throne following the death of King Viserys. Both Princess Rhaenyra, who was daughter to his first wife and named heir, and Prince Aegon II, the firstborn son of his second wife Alicent Hightower, claimed the throne for themselves.

Lord Corlys Valaryon, a.k.a. the Sea Snake, served as Rhaenyra's Hand of the Queen. As for Daemon Targaryen, to be played by Matt Smith, his role in the show should be significant if the show follows Fire & Blood. The first look at House of the Dragon indicates that there should be some dragon action involving Daemon, who ultimately supports his niece (and wife) Rhaenyra's claim.

Now, the fact that Paddy Considine has been cast as King Viserys, Alicent's status as Viserys' wife isn't confirmed, and there is no mention of Aegon suggests that House of the Dragon at least starts with some time to spare before the Dance of the Dragons kicks off.

That said, if House of the Dragon is going to cover the Dance of the Dragons as seems likely, and if it is going to do so without any gigantic time jumps, then I'm guessing that Viserys and Alicent are already married and parents to Aegon, and Aegon simply hasn't been cast yet. I've actually suspected ever since Paddy Considine was announced as Viserys that House of the Dragon would follow a similar format to Game of Thrones as far as the lead character's longevity is concerned.

The death of Ned Stark in the penultimate episode of Game of Thrones' first season was arguably the most game-changing twist of the whole series, as it set events in motion that would lead to the War of the Five Kings and everything that followed. The action of Game of Thrones didn't really pick up until poor Ned lost his head, and the same could be true of House of the Dragons and the death of King Viserys.

That's not to say that King Viserys will be executed at any point, but his death toward the end of the first season could result in two claimants to the throne either heading into Season 2 or in early Season 2. Stannis Baratheon didn't debut until the beginning of Season 2; could the same happen with Aegon, who was simply not present at the Red Keep during House of the Dragon's ten-episode Season 1?

We can only speculate at this point, and it may be a while before we get any more clues short of Aegon being cast. Production is only beginning in 2021; the House of the Dragon premiere may well not air until 2022 at some point. For now, you can always rewatch the eight seasons of Game of Thrones for some Westeros action on HBO Max, and/or check out George R.R. Martin's Fire & Blood in lieu of The Winds of Winter.

If you're in the market for some TV content set elsewhere than the Seven Kingdoms, be sure to check out our 2021 winter and spring premiere schedule.

Laura Hurley
Senior Content Producer

Laura turned a lifelong love of television into a valid reason to write and think about TV on a daily basis. She's not a doctor, lawyer, or detective, but watches a lot of them in primetime. Resident of One Chicago, the galaxy far, far away, and Northeast Ohio. Will not time travel and can cite multiple TV shows to explain why. She does, however, want to believe that she can sneak references to The X-Files into daily conversation (and author bios).