HBO drama Game of Thrones will soon be expanding its vibrant universe even further, as prequel series House of the Dragon is officially in production.

The network has shared a first look at crew and casting, holding a socially-distanced table read with stars Paddy Considine, Emma D'Arcy and Matt Smith.

Matt Smith as Prince Daemon Targaryen.
The @HBO original series #HouseoftheDragon is officially in production and coming to @HBOMax in 2022. pic.twitter.com/7TLn4cSru5

— House of the Dragon (@HouseofDragon) April 26, 2021

House Of The Dragon is set 300 years before the events of Game Of Thrones and will tell the story of the Targaryen family.

The spin-off show confirmed a number of casting reports on Twitter by sharing close-up images of some of the cast members, revealing details of who they will play.

Truth Seekers actress Emma D'Arcy will play Princess Rhaenyra Targaryen, while The Outsider star Paddy Considine takes on the role of her father, the "warm, kind, and decent" King Viserys Targaryen.

Paddy Considine as King Viserys Targaryen.
The @HBO original series #HouseoftheDragon is officially in production and coming to @HBOMax in 2022. pic.twitter.com/ZtS8zpkfS1

— House of the Dragon (@HouseofDragon) April 26, 2021

Doctor Who and The Crown actor Matt Smith has been cast as Prince Daemon Targaryen, the king's younger brother.

Elementary and Harry Potter star Rhys Ifans is playing Otto Hightower, Hand of the King and close counsellor of King Viserys, while Ready Player One actress Olivia Cooke is portraying the role of Otto's daughter, Alicent Hightower.

Doctors and It's A Sin actor Steve Toussaint is playing legendary seafarer The Sea Snake, whose real name is Lord Corlys Velaryon.

Rhys Ifans as Otto Hightower.
The @HBO original series #HouseoftheDragon is officially in production and coming to @HBOMax in 2022. pic.twitter.com/bzqrG1vYic

— House of the Dragon (@HouseofDragon) April 26, 2021

Also set to appear in the series are Nurse Jackie's Eve Best, who will feature as Princess Rhaenys Velaryon, and Crazy Rich Asians star Sonoya Mizuno - who has been cast as Prince Daemon's ally, Mysaria.

House of the Dragon tell the story of Daenerys Targaryen's ancestors as their House begins to fall apart and the Dance of the Dragons civil war begins. Origin stories for different iconic houses of Westeros will also be shared, as well as the tale of how King's Landing was built.

The show has been created by Game of Thrones writer George RR Martin and Colony creator Ryan Condal, with the prequel based on Martin's companion book Fire and Blood.

Condal will serve as showrunner alongside director Miguel Sapochnik, who directed the 'Battle of the Bastards' and 'Hardhome' episodes of GOT.

House of the Dragon will arrive on HBO screens in 2022.