Martell is the brother of Elia Martell, who was killed at the bidding of the House of Lannister during the sack of King's Landing, before the events of the TV series.
The Red Viper will no doubt seek revenge. This is, after all, "Game of Thrones."
Pascal's previous small screen credits include brief appearances on CBS' "The Good Wife" and USA's "Graceland."
"Game of Thrones" recently wrapped up its third season, and will likely make its return sometime in the spring of 2014.
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