The third season of 'Game of Thrones' is going to be bonkers, guys. Those who have read the novels know just how good the third book, 'A Storm of Swords,' is, but new viewers are in for a harrowing treat. Like with season two, season three will add a whole bunch of new faces to Westeros, because 847 major characters just aren't enough. When the show returns sometime in 2013, be prepared to expand your knowledge of Westerosi family trees and memorize a bunch of new names.

First, British actor (aren't they all?) Clive Russell has been cast as Brynden “The Blackfish” Tully, beloved uncle to Catelyn Stark and badass knight of Riverrun. As his name suggests, he's sort of the black sheep of the Tully family. This is a terrific character, one that Russell, a veteran character actor that American audiences may recognize from a small role in 'Sherlock Holmes: A Game of Shadows,' will have a great time with.

Other folks are rumored to have joined the cast, but their exact involvement is uncertain at the time of this writing.

Mackenzie Crook, best known for playing Gareth in the BBC version of 'The Office' and Ragetti in the 'Pirates of the Caribbean' films, is rumored to have been cast in an unspecified role. Although he has frequently been fancast as a villain named Vargo Hoat, that is apparently not the role he is up for.

Charlotte Hope, a young actress whose past credits include the BBC series 'Missing' and 'Waking the Dead,' has been cast as Myranda, a character that many think is a new creation for the series.

Sarah Bolger, who played Mary Tudor in 'The Tudors,' is apparently up for a role (and she will not be the first 'Tudors' actress to join the cast, following in the footsteps of Natalie Dormer).

Finally, Nathalie Emmanuel, who spent three years on the British series 'Hollyoaks,' is also up for a role.

Not too many big names in that list, but 'Game of Thrones' is a show that won its audience with clever plotting and compelling stories (and copious amounts of gore and sex), not star power. With filming on the new season set to commence soon, expect a whole bunch of new names to be announced in the coming weeks.

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