It looks as if Richard E Grant has joined the cast of Game Of Thrones, making him the fifth new name added ahead of the upcoming sixth season. At the moment, who he will be playing in the show remains undisclosed.

Whilst nothing has been confirmed by HBO or Grant himself yet, community fan-site Watchers On The Wall noticed that Thrones had been added to his agency CV, more recently than his latest titles Dig and Jekyll And Hyde. This gives a pretty good indication that the Withnail And I actor will be popping up at some point over the next series.

Now that the television series has caught up with George R R Martin's A Song Of Ice And Fire novels, it's harder to predict who Grant may be playing. Fans have no existing guidance to go by in terms of where the story will go or which characters will play a predominant role in the next instalment.

Online speculation has been suggesting that the 58-year-old could portray archmaster of the Citadel, Maester Marwyn or Lord Paxter Redwyne, both of which feature in the books but have yet to make it onto screen. Redwyne, in particular, has been mentioned in passing on the show and is directly linked to the Tyrells, so it seems as if he may be the more likely candidate. According to recent casting and rumours, the Tarlys and the Greyjoys are going to be of "key importance" come season six, so there's every possibility that Grant might be playing a member of either of those families instead.

However, he also fits this casting call that the hugely-popular fantasy series released recently very well: "Grand Theatre Actor/Manager (55 – 70) The larger-than-life leader of a troupe of actors. He specialises in portraying drunken aristocrats. He is a huge presence on stage and rather nasty to his company when off-stage."

Other names that have been added to the ever-growing cast list ahead of the new season include fellow English actors Freddie Stoma and Ian McShane, as well as Swedish-French star Max von Sydow and Danish actor Pilou Asbæk. Stoma will be playing Samwell Tarly's brother Dickon, whereas Asbæk will bring Euron Greyjoy to life. Sydow will be replacing previous Thrones actor Struan Rodger as the Three-Eyed Raven and McShane's role, like Grant's, remains unknown.