‘House Of the Dragon’: Rhys Ifans, Steve Toussaint, Eve Best & Sonoya Mizuno Join HBO’s ‘Game of Thrones’ Prequel

HBO’s House of the Dragon has rounded out its main cast with the addition of Rhys Ifans, Steve Toussaint, Eve Best and Sonoya Mizuno.

They join Paddy Considine, Olivia Cooke, Matt Smith and Emma D’Arcy in the straight-to-series Game of Thrones prequel from George R.R. Martin, Ryan Condal and Miguel Sapochnik.

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Based on Martin’s Fire & Blood, the series, which is set 300 years before the events of Game of Thrones, tells the story of House Targaryen. I hear the series has five lead characters: King Viserys Targaryen (Considine), Alicent Hightower (Cooke), Princess Rhaenyra Targaryen (D’Arcy), Prince Daemon Targaryen (Smith) and Lord Corlys Velaryon (Toussaint), known as the Sea Snake, who becomes Hand to Queen Rhaenyra Targaryen during the Dance of the Dragons.

Toussaint’s Lord of House Velaryon comes from a Valyrian bloodline as old as House Targaryen. As “The Sea Snake,” the most famed nautical adventurer in the history of Westeros, Lord Corlys built his house into a powerful seat that is even richer than the Lannisters and that claims the largest navy in the world. Danny Sapani was previously in talks for the role.

Ifans will play Otto Hightower. The Hand of the King, Ser Otto loyally and faithfully serves both his king and his realm. As the Hand sees it, the greatest threat to the realm is the king’s brother, Daemon, and his position as heir to the throne.

Best is cast as Princess Rhaenys Velaryon. A dragonrider and wife to Lord Corlys Velaryon, “The Queen Who Never Was” was passed over as heir to the throne at the Great Council because the realm favored her cousin, Viserys, simply for being male.

Mizuno plays Mysaria, who came to Westeros with nothing and has been sold more times than she can recall. She could have wilted… but instead she rose to become the most trusted — and most unlikely — ally of Prince Daemon Targaryen, the heir to the throne.

House of the Dragon was co-created by Martin and Condal. The pilot script that landed the series order was written by Condal. He serves as co-showrunner alongside GoT veteran Miguel Sapochnik, who will direct the pilot and additional episodes. Martin, Condal and Sapochnik executive produce alongside writer Sara Lee Hess, Vince Gerardis and Ron Schmidt. Greg Yaitanes co-executive produces. Yaitanes, Clare Kilner and Geeta V. Patel round out the 10-episode series’ directing team.

Ifans, known for his roles in Notting Hill, the Spider-Man and Harry Potter franchises, will next be seen in Matthew Vaughn’s latest Kingsman: The Great Game. He was recently seen in the historical-comedy drama film Misbehavior, starring alongside Kiera Knightly and Keeley Hawes, released March 2020. In 2019 Ifans completed a main stage run of On Bear Ridge at The Royal Court. Ifans is represented by Kate Buckley at 42, Brillstein Entertainment Partners and Gersh.

Toussaint is seen in Steve McQueen s acclaimed film Red, White and Blue, part of the Small Axe series, and Channel Four’s It’s a Sin, which will launch on HBO Max. On stage, Toussaint most recently played the lead in Father Comes Home From the Wars at The Royal Court Theatre Toussaint is repped by CDA London.

On stage, Best has been honored with the Evening Standard Award for Outstanding Newcomer in Tis Pity She’s A Whore, and the Olivier Award for Best Actress playing the title role in Hedda Gabler. On Broadway she received Tony nominations for the revivals of A Moon for the Misbegotten and The Homecoming. In television and film Best is known for her roles in Nurse Jackie, The Honorable Woman and The King’s Speech. Best is represented by Independent Talent Group and ICM Partners.

Mizuno recently starred in FX’s Devs. She is currently in production on the feature Am I OK, in which she co-stars opposite Dakota Johnson. Prior to transitioning to acting, Mizuno graduated from the Royal Ballet School and danced in Arthur Pita’s “The World’s Greatest Show” at the Royal Opera House. Mizuno is repped by United Agents, WME and Goodman Genow Schenkman.

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