Warning! Possible SPOILERS for House of the Dragon from the Fire and Blood source material ahead.The Game of Thrones prequel series House of the Dragon has assembled an impressive cast, bringing to life even more characters - including plenty of Targaryens - from the world of Ice and Fire created by George R.R. Martin. The House of the Dragon cast reveals more members of the Targaryen family tree who lived (and died) some 200 years before the events in the original series. Based on characters from George R.R. Martin's Fire & Blood novel, the Game of Thrones prequel cast leads audiences through a deep dive into the history of Westeros' dragonriders, about a century after Aegon's Conquest united the Seven Kingdoms under the banner of House Targaryen. House of the Dragon, was developed by Martin himself alongside Ryan Condal, with the latter serving as showrunner alongside longtime Game of Thrones director Miguel Sapochnik. Other key players returned too, including composer Ramin Djawadi.

Outside of production, however, the House of the Dragon cast is composed of all new characters. Moreover, as some House of the Dragon's season 1 episodes are divided by massive time jumps, the Game of Thrones prequel cast includes different actors for younger and older versions of certain characters. This can be observed in the House of the Dragon episode 6 cast, in which the series jumped a full 10 years into the future, and several main characters were recast with more mature actors to reflect the passage of time. Here's everything viewers need to know about the Game of Thrones prequel cast and characters.

Related: Complete House Of The Dragon Guide: All Your Questions Answered

House Targaryen Characters In House Of The Dragon

Unlike Game of Thrones which featured only the last three living Targaryens in its timeline - Daenerys, Maester Aemon, and Jon Snow - the House of the Dragon cast is composed mostly of members of House Targaryen. In House of the Dragon, the Targaryens have ruled Westeros for over a century, with the series beginning in the latter end of the relatively peaceful rule of King Viserys I Targaryen. Here's every Targaryen in House of the Dragon.

Paddy Considine as Viserys I Targaryen

The grandson of Jaehaerys I Targaryen, King Viserys I Targaryen has to not only succeed the former King, but live up to his standards. Jaehaerys is generally recognized as one of the greatest kings to ever sit on House of the Dragon's Iron Throne, which, in the prequel, has way more melted swords and looks much closer to its intimidating description in the books. Played by veteran British actor Paddy Considine, who has been critically praised for his outstanding performance in the Game of Thrones prequel, Viserys bears the weight of fulfilling House Targaryen's role in Aegon's prophecy, all while trying to prevent a war of succession between the other House of the Dragon cast members. Indeed, unlike many of the other Targaryen kings referenced in Game of Thrones, Viserys himself is a rather peaceful man who dislikes conflict, and his reign is mostly a peaceful and prosperous era. Viserys' actions do, however, lead to the Dance of the Dragons in the wake of his death. Viserys is also the last dragonrider of the great Balerion the Dread, who was bigger than any of the dragons in House of the Dragon, and whose skull was shown in the crypts of the Red Keep.

Milly Alcock/Emma D'Arcy as Rhaenyra Targaryen

Milly Alcock and Emma D'Arcy as Rhaenyra Targaryen

As the firstborn child of Viserys I Targaryen, Princess Rhaenyra Targaryen is a key player in the House of the Dragon cast. Rhaenyra was named Viserys' heir after the death of Baelon, Viserys' second son. Viserys' first son died during infancy like Baelon, while their mother, Aemma, also passed away. Her appointment to the Iron Throne was an unusual move at the time, done in part to spite those who mocked the death of Baelon, and it ultimately gave Westeros its first ruling Queen. In House of the Dragon, Rhaenyra spends most of her childhood preparing to succeed her father and maintain her position as heir even after Viserys re-marries Alicent Hightower and has several more sons. After Rhaenyra is named Princess of Dragonstone at the age of 16, Rhaenyra marries Laenor Velaryon, with whom she has three sons, although the marriage was, as is often the case in Westeros, one built for political and strategic gain than out of love.

After Laenor was killed in Fire & Blood - a fate which changes in House of the Dragon - Rhaenyra marries her uncle, Daemon Targaryen. Following Viserys' death, Daemon supports Rheanyra's claim to the Iron Throne, which is challenged by her younger half-brother, Aegon - Alicent and Viserys' first son. This split is what leads to the Dance of the Dragons, the Targaryen Civil War that divides Westeros into two factions – the greens (supporting Aegon) and the blacks (supporting Rhaenyra) – and ultimately sees Viserys' named heir Rhaenyra crowned Queen of the Seven Kingdoms - at least from the blacks' point of view. Described as beautiful, stubborn, and quick-tempered, Rhaenyra is played by Milly Alcock during the first half of House of the Dragon, and then by Emma D'Arcy from episode 6 onwards.

Related: Why Rhaenyra Considers Alicent's Offer & Doesn't Just Kill Otto

Matt Smith as Daemon Targaryen

An image of Daemon Targaryen in House of Dragon

Prince Daemon Targaryen is the younger brother of Viserys, and a complicated character in his own right. While Daemon supports his brother's claim to the Iron Throne at the Great Council, he largely does so out of his own lofty ambitions, believing it will place him next in line if Viserys fathers no sons. Daemon and King Viserys have an often-fractious relationship, which isn't helped by the former's rivalry with the Hand of the King, Otto Hightower. House of the Dragon's Daemon Targaryen is regarded as one of the greatest warriors of his age, although he's also strong-willed, roguish, and bad-tempered. For a time, Daemon rules as the self-proclaimed King of the Stepstones and the Narrow Sea, but eventually gives up the mantle to rejoin his brother's side and take a place on the small council.

That itself doesn't last long, though, as rumors of Daemon taking Princess Rhaenyra's virginity before her 16th birthday leads to his exile on the King's orders. This saga would go on, with Daemon eventually winning back his brother's favor and returning; eventually, he marries Rhaenyra, albeit without Viserys' knowledge. After the King's death, Daemon declares Rhaenyra as the rightful Queen of the Seven Kingdoms, standing proudly by her wife and queen's side at the very forefront of the war that ensued. In House of the Dragon, Daemon Targaryen is played by Matt Smith, best known as the Eleventh Doctor in Doctor Who.

Ty Tennant/Tom Glynn-Carney as Aegon II Targaryen

Aemond behind Aegon in House of the Dragon

Aegon II Targaryen is Viserys and Alicent's firstborn son. While Aegon and Rhaenyra are siblings, they form no real relationship save for the enmity caused by their latter conflicting claims to the Iron Throne. Despite being named after the greatest conqueror in the history of Westeros, Aegon was mostly concerned with bedding women in his youth, earning him a lustful reputation among the common folk and nobility alike. Though reluctant to rule at first, Aegon eventually accepts Alicent and Otto Hightower's wishes for him to sit on the Iron Throne following the death of King Viserys I Targaryen, setting the stage for the Targaryen civil war, also known as the Dance of the Dragons. First appearing in the House of the Dragon cast as an infant, Aegon II Targaryen is played by Ty Tennant during his younger years, and then by Tom Glynn-Carney in the latter half of the first season.

Minor Targaryens in House of the Dragons

Aemond Targaryen looking shocked in House of the Dragon season 1 finale

Like Game of Thrones, House of the Dragon features an ensemble cast, with several minor characters. While Viserys, Daemon, Rhaenyra, and Aegon are the main Targaryens of season 1, there are many other Targaryens in House of the Dragon. Here are the other members of House Targaryen in the Game of Thrones prequel cast:

Related: How Aegon's Dream Completely Changes HOTD's Targaryen & Stark Pact

  • Aemond Targaryen is played by Ewan Mitchell. Aemond Targaryen is the third child and second son of Viserys, is Rhaenyra's half-brother, and wears a distinctive eyepatch. The actions of Aemond Targaryen and his dragon Vhagar, the largest living dragon in House of the Dragon, are partly responsible for setting off the Dance of the Dragons.
  • Helaena Targaryen is played by Phia Saban. Helaena Targaryen is the daughter of Viserys and Alicent Hightower, making her Aegon and Aemond's sister. In the Fire and Blood book, Helaena is described as being notably liked by the common people throughout Westeros.
  • Baela Targaryen is played by Bethany Antonia. She is Daemon's daughter, and her mother is Laena Velaryon. In the books, she and her sister Rhaena were twins, but this has been changed for House of the Dragon, and Baela is now Rhaena's older sister.
  • Rhaena Targaryen is played by Phoebe Campbell. She is Baela's younger sister but was her twin in George R. R. Martin's story Fire and Blood.

House Hightower Characters In House Of The Dragon

Alicent and Otto Hightower in House of the Dragon

House Hightower is a vassal house hailing from the Reach that swears fealty to a now-extinct Game of Thrones house — the Tyrells, the notorious thorns in the Lannisters' sides. House Hightower's sigil is, fittingly, a tower. House Hightower is another key family in House of the Dragon, mainly due to Alicent Hightower, who is married to Viserys Targaryen. Her relationship with Rhaenyra is a key feature of the show, as is her father Otto, who is the Hand of the King. Here's everything audiences need to know about the characters from House Hightower in the House of the Dragon cast.

Emily Carey/Olivia Cooke as Alicent Hightower

The second wife of King Viserys I Targaryen, Alicent Hightower is the daughter of Otto, Viserys' Hand. A close companion of Jaehaerys before his death, Alicent remained a constant figure in King's Landing throughout the reign of King Viserys, and, when it eventually came time for him to wed again, he chooses Alicent as his new bride despite Rhaenyra and the small council's objections. Alicent Hightower and Rhaenyra Targaryen's rivalry serves as the very roots of the Targaryen civil war that brews in House of the Dragon season 1. With both women setting eyes on the throne, the resentment between them grows when Rhaenyra remains the King's heir despite Alicent giving him several sons. Alicent is an intelligent, shrewd operator who grew up watching the political machinations of the kingdom, and when Viserys died - with Rhaenyra away on Dragonstone - she quickly makes a move to install her own son, Aegon, as the new King.

Rhys Ifans as Otto Hightower

The father of Alicent, Otto Hightower serves as the Hand of the King, a job he dutifully performed for Jaehaerys I and continued to do so for Viserys when he took the crown. The head of House Hightower of Oldtown, House of the Dragon's Otto Hightower is a master manipulator who becomes crucial to Aegon's ascension to the Iron Throne. Otto's ambition leads Viserys to strip him of his title as the Hand, only to resume the role later when his replacement dies of mysterious circumstances. Following the death of King Viserys, Otto continued to serve as the Hand of the King, this time for his grandson Aegon II. Otto is played by The Amazing Spider-Man actor Rhys Ifans.

Related: You May Hate Him, But Otto Hightower Is Right In HOTD Episode 5

House Velaryon Characters In House Of The Dragon

House Velaryon is the second most prominent house in House of the Dragon, second only in the number of characters to the Targaryens themselves. Driftmark is their seat of power, and their sigil is a majestic horse with the lower half of a fish. The Velaryons and Targaryens are connected both by marriage and a shared heritage - the only Westerosi families with dragonriders who can claim to hail from the blood of Old Valyria. In fact, House Velaryon's dragons comprise half of the living dragons in Westeros in the House of the Dragon timeline. The Velaryons are a seafaring people and their leader, Corlys Velaryon, holds the official title of Lord of the Tides. Here's everything else viewers need to know about the House Velaryon characters in the Game of Thrones prequel cast.

Steve Toussaint as Corlys Velaryon

A closeup of Corlys Velaryon in House of the Dragon

Also known as the Sea Snake, after his ship of the same name, Corlys Velaryon is the head of House Velaryon which, like House Targaryen, is Valyrian in origin. A brilliant sailor, Corlys was said to be incredibly adventurous and journeyed well beyond the lands and waters of Westeros, which brought him great prosperity. Corlys' voyages made him the stuff of legend in Westeros, but he also had his own ambitions on land, which included marrying Princess Rhaenys Targaryen - the daughter of Aemon and granddaughter of King Jaehaerys. Corlys was slighted several times following this. Princess Rhaenys Targaryen was overlooked as Queen, and their son Laenor was passed over in favor of Viserys to become King. Then, when Viserys remarried, he chose Alicent Hightower instead of their daughter, Laena. This led to an angry Corlys teaming up with Daemon Targaryen, helping him claim the Stepstone crown.

However, one of Corlys' offspring eventually married a Targaryen, as Laenor later wed Princess Rhaenyra, having several children before his death (although the kids themselves are rumored to have been fathered by Ser Harwin Strong). In the book Fire & Blood, Corlys supports the claim of Rhaenyra and serves as Hand of the Queen - but later betrays her for Aegon II, which could transpire in House of the Dragon season 2. A key member of both the greens and blacks in House of the Dragon, Corlys Velaryon is played by Steve Toussaint, who has appeared in a multitude of British TV shows including Doctor Who, Skins, and It's A Sin.

Eve Best as Rhaenys Velaryon

Alongside Corlys in House of the Dragon is Princess Rhaenys Targaryen, also known as the Queen Who Never Was due to her being thought to have been next in line for the Iron Throne following her father, Aemon, who was the son of Jaehaerys. Combining the purple eyes of a Targaryen with the black hair of a Baratheon (Rhaenys' mother was Jocelyn Baratheon), Rhaenys was considered a great beauty, as well as someone possessing considerable intellect. Rhaenys was passed over for the crown by King Jaehaerys who, following the death of Aemon, had to appoint a new heir; the King chose his second son, Baelon, instead, much to the anger of Rhaenys and her husband, Corlys. During the Dance of the Dragons in Fire & Blood, Princess Rhaenys and her dragon Meleys are loyal to the blacks and Queen Rhaenyra, serving on her council before her death. Rhaenys is played in House of the Dragon by Eve Best, who is known for her role as Dr. Eleanor O'Hara in Nurse Jackie.

Related: Where Was House Of The Dragon Filmed? All Real Life Westeros Locations

Minor Velaryons in House of the Dragons

Steve Toussaint as Corlys Velaryon in HOTD

Corlys and Rhaenys aren't the only Velaryons in House of the Dragon. While not well known to Game of Thrones fans (those who haven't read the A Song of Fire and Ice books, at least), many are dragonriders like the Targaryens. House Velaryon plays an integral role in the House of the Dragon plot, so there are naturally a fair few members among the show's character roster. Here are the minor and lesser-known Velaryon characters in House of the Dragon.

  • Laena Velaryon is played by Savannah Steyn. Laena is Corlys' and Rhaenys' daughter. She is a dragonrider and was described in Fire and Blood as being known for her exceptional beauty. Laena Velaryon was dragonrider to Vhagar.
  • Laenor Velaryon is played by John Macmillian and Theo Nate, depending on which House of the Dragon timeline the scene is in. Laenor is Laena's brother and also a dragonrider. Laenor ends up becoming Rhaenyra's first husband, and they have three children (including one Velaryon who shares a name with Game of Thrones' Joffrey).
  • Vaemond Velaryon is played by Wil Johnson. The younger brother of Corlys, Vaemond is the commander of the Velaryon navy - the largest and most formidable fleet in all of Westeros. His character has already been changed from the books, as in Fire and Blood Vaemond is Corlys' nephew, with the Sea Snake's younger brother never named.
  • Jacaerys Velaryon is played by Harry Collett. Jazaerys is the son of Rhenyra Targaryen and Laenor Velaryon. He grows up to take part in the Dance of the Dragons, and like his family on both sides, he was a dragonrider. House of the Dragon's Jacaerys Velaryon and Vermax, his dragon, were last seen riding to the Vale to gather support for Rhaenyra's claim.

Other Important Characters House Of The Dragon

There were many characters in Game of Thrones, such as Bronn, Greyworm, and Sandor Clegane/The Hound, who didn't belong to a notable house (or were unaffiliated with one that had a major bearing on the show), and the same is true of House of the Dragon. Two characters, in particular, the spy Mysaria and the Dornish knight Ser Criston Cole, belong to this category. Here's everything to know about Mysaria and Ser Criston Cole in House of the Dragon.

Sonoya Mizuno as Mysaria

Serving as something akin to the Varys of House of the Dragon, Lady Mysaria hails from Lys, and was the former consort and advisor of Prince Daemon Targaryen, before Mysaria became House of the Dragon's White Worm. Like Varys, Mysaria uses the children and other denizens of Flea Bottom as her informants within and beyond King's Landing, even feeding information to the Red Keep's nobility whenever it aligns with her own interests, though this eventually puts her at odds with Otto Hightower. In Fire & Blood, Mysaria becomes the master of whisperers to Queen Rhaenyra of the blacks. Sonoya Mizuno, who has been a frequent collaborator of Alex Garland, appearing in Ex Machina, Annihilation, and Devs, plays Mysaria in House of the Dragon.

Related: House Of The Dragon: Every Major Family Missing From Game Of Thrones

Fabien Frankel as Criston Cole

Another major character in House of the Dragon is Criston Cole, who is played by Fabien Frankel, whose previous credits include Fabien in Last Christmas and Dominique Renelleau in The Serpent. Ser Criston Cole's sheer skill in melee combat makes him comparable to the best knights in Westeros, and eventually allows him to rise to the position of Lord Commander of Viserys I's Kingsguard, and even defeat Daemon Targaryen in tourneys. In Fire & Blood, there were rumors of an affair between Criston and Rhaenyra, and, like the claims of a romance between the Princess and Harwin Strong, these claims are substantiated in House of the Dragon. After Criston is rejected by Rheanyra, he aligns himself to the cause of Alicent Hightower, and has been loyal to her ever since, including during the Dance of the Dragons.

Other Characters In House Of The Dragon (Including Starks and Lannisters)

In Game of Thrones, there were characters from many of the different major and minor houses that make up the nobility of Westeros. House of the Dragon focuses on the Targaryens, Velaryons, and Hightowers instead of the Starks and Lannisters from Game of Thrones. However, ancestors of both the main houses in Game of Thrones feature in the prequel, as do names and faces from new families not yet seen in any TV adaptation of a George R. R. Martin book. Here are all the minor characters in the House of the Dragon cast.

  • Jason Lannister and Tyland Lannister, who are twins, are both played by Jefferson Hall. The Lannisters aren't the powerhouses Game of Thrones fans will be used to seeing, and in House of the Dragon, the Lannister twins scheme to advance the Casterly Rock clan's fortunes and capitalize on the chaos that sweeps Westeros during the brewing war of succession.
  • Lyonel Strong is played by Gavin Spoakes. Lord Lyonel Strong is the Lord of Harrenhal at the beginning of House of the Dragon, and even becomes Hand of the King after Otto Hightower is stripped of the title. House of the Dragon episode 6's deaths include Lyonel and his son Harwin, who perish in a fire at Harrenhal like their counterparts in the book.
  • Harwin "Breakbones" Strong is played by Ryan Corr. Harwin is the eldest son of Lord Lyonel. He's also fittingly named, as he's said to be the strongest man in the Seven Kingdoms. While Fire & Blood only implies that Harwin is the true father of Rhaenyra's Velaryon sons, House of the Dragon confirms this as fact.
  • Larys Strong is played by Matthew Needham. Larys is one of Lord Lyonel's younger sons, he eventually becomes Viserys' Master of Whisperers in the original Fire and Blood story, a role that Larys also steps into in the show.
  • Grand Maester Mellos is played by David Horovitch. Mellos is one of Viserys' most trusted advisors and fills a role similar to that of Grand Maester Pycelle in Game of Thrones. Mellos is ultimately unable to stop King Viserys' disease from consuming the king.
  • Harrold Westerling is played by Graham McTavish. Ser Harrold is a knight of the Kingsguard. He only has a few mentions in the books, but the HBO series portrays him as a chivalrous and honorable character.
  • Lyman Beesbury will be played by Bill Paterson. Lyman Beesbury, the Lord of Honeyholt, sits on the King's council as the Master of Coin. Paterson is most known for his role as Dad in Fleabag but has a career spanning decades, making him one of the most experienced actors in the extensive House of the Dragon cast.

Has House Of The Dragon Changed The Characters From The Book?

Rhaenyra Targaryen and Alicent Hightower with catspaw dagger in House of the Dragon

House of the Dragon is largely faithful to the book - but with several changes, most notably in how the show fleshed out Rhaenyra and Alicent's relationship, and how it added the detail of Aegon the Conqueror's dream/prophecy as the primary reason for why House Targaryen maintained its three-century dynasty. Indeed, though Rhaenyra Targaryen and Alicent Hightower didn't have any real relationship prior to the Dance of the Dragons in Fire & Blood, they are childhood friends in House of the Dragon. This actually makes sense, as the rift that grew between Rhaenyra and Alicent is essentially what sparked the Targaryen civil war, and putting a focus on their relationship further contextualizes the historic event.

Related: What Otto Gives To Rhaenyra From Alicent & What It Means

Next to this, perhaps the biggest change to the book is how Viserys reveals to Rhaenyra that Aegon the Conqueror foresaw the long night and prophesied that a Targaryen must be on the Iron Throne in order to protect and "unite the realm against the cold and the dark" - a message hidden in Old Valyrian on the blade of Game of Thrones' catspaw dagger. There is actually no mention of Aegon's dream/prophecy nor of Viserys' dagger, which Arya used to kill the Night King in Game of Thrones, in the book. This is a major change that not only connects Game of Thrones to House of the Dragon, but also consequently serves as the reason why Alicent believes Viserys wanted Aegon II on the Iron Throne before he died.

House of the Dragon changes many other aspects of the characters from Fire & Blood, but this doesn't necessarily mean that it's not a faithful adaptation of the novel. As Fire & Blood was written as a historical account, it can be argued that the events shown in the House of the Dragon timeline are what actually happened, and full of details missed by the maesters who wrote the book based on several sources. More importantly, unlike Game of Thrones, George R.R. Martin himself has a hand in crafting the plot of the prequel series, which means that these changes come with the author's blessing. While the show takes plenty of liberties when it comes to interpreting book events, its story stays true to the overarching plot of Fire & Blood, and House of the Dragon season 2 is bound to finally show what happens in the Dance of the Dragons.

Next: Every House Of The Dragon Change From The Book So Far