A key role for Game of Thrones upcoming fourth season has officially been cast.

British actor Struan Rodger will be playing the Three-Eyed Raven, the presumed bird that haunts Bran's (Isaac Hempstead-Wright) dreams. The Three-Eyed Raven is known as the Three-Eyed Crow in the A Song of Ice and Fire books on which the series is based.

Avid readers of the books know that the Three-Eyed Crow finally reveals himself to be a man after Bran and company travel north of the Wall. News of Rodger's casting as the Three-Eyed Raven was discovered by Game of Thrones fansite WinterisComing.net. The actor added the role to his online resume.

What is arguably most intriguing about this casting news is that the Three-Eyed Raven does not appear in human form until book 5, A Dance with Dragons. This may indicate that season 4 will go well beyond adapting the end of book 3, A Storm of Swords, which had previously been announced.

Game of Thrones Season 4 Spoilers: Show Adapting Books 4 & 5 in Spring 2014 Episodes? [VIDEO]

In A Dance with Dragons, Bran and his band of misfits travel to a cave in the haunted forest where they meet the Three-Eyed Raven. The raven reveals himself to actually be a man who was once a lord named Brynden. Bran is disappointed to learn that the Raven cannot help fix his crippled legs.

Season 4 of Game of Thrones does not have a scheduled premiere date yet but it is expected to debut in the spring of 2014.

Game of Thrones Season 4 Spoilers: George R. R. Martin Talks Purple Wedding Details [VIDEO]

Watch this video detailing the numerous new characters that will be introduced in season 4: