'Game of Thrones' Prequel Cast: Who is Rhaenyra Targaryen?

HBO is moving forward with its second attempt at a Game of Thrones prequel spin-off titled House of the Dragon—and some interesting casting news has reached the fandom.

The series was first announced last October when HBO said there would be "a 10-episode, straight-to-series order" for a show centering around the Targaryen dynasty, which is good news for Daenerys (played by Emilia Clarke) fans.

Now the search is on to find an actress to fill the role of the legendary Queen of Dragons Rhaenyra Targaryen.

Casting rumors began circulating on fans sites Redanian Intelligence and the Wertzone but now a source has confirmed to Insider that the process is now underway.

The synopsis for House of the Dragon according to HBO reads: "Based on George R.R. Martin's "Fire & Blood," the series, which is set 300 years before the events of Game of Thrones, tells the story of House Targaryen. Miguel Sapochnik will direct the pilot and additional episodes. Ryan Condal and Sapochnik will partner as showrunners on the series, which will be written by Condal."

#HouseOfTheDragon, a #GameofThrones prequel is coming to @HBO.

The series is co-created by @GRRMSpeaking and Ryan Condal. Miguel Sapochnik will partner with Condal as showrunner and will direct the pilot and additional episodes. Condal will be writing the series. pic.twitter.com/9ttMzElgXm

— Game of Thrones (@GameOfThrones) October 29, 2019

Sapochnik is known for directing some pivotal Game of Thrones episodes such as "Hardhome" in 2015 and "Battle of the Bastards" in 2016. He also is partly responsible for some Season 8 episodes, like the much-maligned, but undeniably action-packed, "The Bells."

Fans may be a little relieved to hear that former showrunners D.B. Weiss and David Benioff will not be on writing duties again after they were heavily criticized for how Game of Thrones Season 8 ended.

Condal, on the other hand, is known for his work on films Rampage (2018) and Hercules (2014) and the USA Network sci-fi series Colony (2016).

This latest round of Westeros-related news comes after the series' first planned spin-off—rumored to have been named Bloodmoon—starring Naomi Watts, was officially shelved in November 2019 after the pilot was filmed last year.

Emilia Clarke as Daenerys Targaryen in episode 6, season 8 of Game of Thrones. HBO

The author of the A Song of Ice and Fire series George R.R. Martin expressed his sadness at the premature cancellation of the fledgling series on his blog at the time: "It goes without saying that I was saddened to hear the show would not be going to series," he wrote. "Jane Goldman is a terrific screenwriter, and I enjoyed brainstorming with her."

Redanian Intelligence did some digging and found that one of the financial controllers who worked on Bloodmoon updated his LinkedIn to say he was now working on an Untitled Game of Thrones Prequel – Red Gun, which is likely a code name for House of the Dragon.

HBO is reportedly looking to cast two major characters Rhaenyra Targaryen and Alicent Hightower.

Also known as the Realm's Delight Rhaenyra, in ASOIAF mythology is the eldest child of King Viserys I Targaryen. Her mother is Dowager Queen Alicent Hightower.

Rhaenyra's claim to the Iron Throne was challenged by her younger half-brother, Aegon II Targaryen, igniting the civil war known as the Dance of the Dragons and [SPOILER ALERT] she eventually was defeated by Aegon II who had his dragon devour her.

As one of the most distinctive figures in Game of Thrones lore, casting for Rhaenyra will certainly be of huge interest to fans.

Clarke was so beloved in the role of her descendant Daenerys, but a relative unknown before the series propelled her to fame. However, the show's success may see the casting directors search for more established actors to fill the part.

While House of the Dragon will center on House Targaryen before the events of Game of Thrones, Bloodmoon was to be set during the Age of Heroes, around 8,000 years before the original TV series, and was planned depict the events of what is known as the Long Night, in the fantasy series' canon.

House of the Dragon is currently in production for HBO.