Stars including Emilia Clarke, Alfie Allen, Nikolaj Coster-Waldau and Charles Dance were joined by showrunners David Benioff and Dan Weiss at the Old Vic Tunnels for the GoT-themed event, which included fire dance displays, female actresses pretending to eat hearts and a replica Iron Throne.
Game of Thrones season one is released worldwide on DVD and Blu-ray on Monday, March 5, 2012.
Season two premieres on April 1 on HBO. It airs a day later in the UK on Sky Atlantic.
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