Entitled 'Molding The Book Into A Series', the featurette sees executive story editor / writer Bryan Cogman (My Own Worst Enemy) explaining the process of adapting George R.R. Martin's A Storm of Swords... well, the first half of it, at least.
Game of Thrones season three sees the return of familiar faces such as Peter Dinklage (Tyrion Lannister), Kit Harington (Jon Snow), Lena Headey (Cersei Lannister), Richard Madden (Robb Stark), Nikolaj Coster-Waldau (Jaime Lannister), Jack Gleeson (Joffrey Baratheon) and Stephen Dillane (Stannis Baratheon), while newcomers to the huge ensemble cast include Diana Rigg (The Avengers), Mackenzie Crook (The Office), Clive Russell (Thor: The Dark World), Thomas Sangster (Nowhere Boy) and Ciarán Hinds (The Woman in Black), who will portray Mance Rayder, a.k.a. the King Beyond the Wall.
Season three gets underway in the States on March 31st on HBO.