Game Of Thrones is a giant hit for HBO and is being treated as such — receiving a two-year renewal a day after the fourth-season premiere delivered the fantasy series’ biggest ratings to date and HBO’s largest audience since The Sopranos finale. This is the first multi-season pickup for Game Of Thrones, which is now assured to run for least six seasons. How far can the hit go seems to be in the hands of the novels’ writer George R.R. Martin, who is still writing Book 6 in the seven-book series. There is breathing room — the current Season 4 chronicles events that take place toward the end of the third book. “Game Of Thrones is a phenomenon like no other,” said HBO programming president Michael Lombardo. “(Creators) David Benioff and D.B. Weiss, along with their talented collaborators, continue to surpass themselves, and we look forward to more of their dazzling storytelling.”

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Based on the bestselling fantasy book series by Martin, Thrones is an epic story of treachery and nobility set on the continent of Westeros, where summers and winters can last years, and only the lust for power is eternal. The Season 4 premiere this past Sunday was watched by an average of 6.6 million viewers, up 52% over last season’s debut and 23% over last season’s finale. The show added an additional 1.6 million viewers from the 11 PM and 1 AM replays, for a gross premiere-night audience of 8.2 million viewers. Season 3 of the series had an average audience of 14.4 million viewers per episode across various platforms. Executive producing Season 4 are Benioff, Weiss, Carolyn Strauss, Frank Doelger and Bernadette Caulfield; co-executive producers are Guymon Casady, Vince Gerardis and George R.R. Martin; and producers are Chris Newman and Greg Spence.