HBO announced 14 new cast members who are coming to Westeros in Season 3 of Game of Thrones. The most notable addition is Diana Rigg from the 1960s The Avengers series, who is playing Lady Olenna Tyrell, a.k.a The Queen of Thorns. Other new cast members include Mackenzie Crook (Orell), Clive Russell (Bryndon "The Blackfish" Tully), Nathalie Emmanuel (Missandei), Kerry Ingram (Shireen), Tara Fitzgerald (Selyse), Paul Kaye (Thoros of Myr), Thomas Sangster (Jojen Reed), Ellie Kendrick (Meera), Richard Dormer (Beric Dondarrion), Kristofer Hivju (Tormund Giantsbane), Philip McGinley (Anguy), Tobias Menzies (Edmure Tully), and Anton Lesser (Qyburn). The studio has also released this video where several of the new cast members talk about their characters.
Game of Thrones Season 3 is currently in production, although a season premiere date has not been announced by HBO as of yet.