Game of Thrones normally uses its Comic-Con panel every summer to announce the new casting additions for each season, but that tradition was broken this year. The show still hasn't made any official casting announcements to date, but news has started to trickle out from unconventional sources. Today, we have a report from Watchers on the Wall, which reveal that veteran British actor Richard E. Grant has signed on for an unspecified role in Season 6. It isn't known if he has started filming or not.

The news of his casting was spotted on the actor's official resume page on his talent agency's website, but the listing was removed shortly thereafter. There are still a number of roles that have yet to be cast, such as Randyll Tarly, the father of Samwell Tarly, Aeron Greyjoy, Lord Karstark and Smalljon Umber, so it's possible that Richard E. Grant could be playing any one of those roles. It's also possible that he could be playing a character created specifically for this new season of Game of Thrones.

If this report is true, Richard E. Grant joins new Game of Thrones cast members such as Ian McShane in an unspecified role, Pilou Asbæk, who has been rumored to be playing Euron Greyjoy, the uncle of Alfie Allen's Theon Greyjoy and Max von Sydow as the Three-Eyed Raven. It isn't known when HBO plans on confirming these actors have been cast, and when they will reveal which characters they are playing.

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It's possible that HBO is being extra secretive in Season 6 because the series has caught up to George R.R. Martin's novels, and since we still have no clue when his sixth novel, entitled The Winds of Winter, will be released. George R.R. Martin recently revealed that he isn't worried that the TV series may end before he actually finishes writing the sixth and seventh books the show is based on. It's possible that the author could release the sixth book before Season 6 debuts sometime next spring, but we don't know for sure.

Richard E. Grant has more than 100 movie and TV credits to his name, with the actor making his feature debut in the critically-acclaimed Withnail & I. Most recently, he had arcs in HBO's Girls and PBS' Downton Abbey, and starred in the event series Dig, which debuted this spring. On the big screen, he played Dickie Black opposite Jude Law in Dom Hemingway. Who do you think Richard E. Grant is playing in Game of Thrones?