Two days after the Season 4 premiere broke Game of Thrones' rating records, HBO renewed the fantasy drama for two more seasons.

"Game of Thrones is a phenomenon like no other," HBO's President of Programming Michael Lombardo said in a statement on Tuesday. "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."

The Game of Thrones' Season 4 premiere, which aired on April 6, brought in 6.6 million viewers, making it HBO's most-watched program since 2007's The Sopranos series finale, which boasted 11.9 million viewers. If the series continues on the trajectory it has in the past, it could very well oust The Sopranos as the highest-rated show ever on HBO.

The Emmy-winning series is based on George R. R. Martin's best-selling A Song of Ice and Fire book series and there's long been fear that the series could catch up with the books. Though the series was originally intended to be a trilogy, it's now intended to be seven volumes, the fifth of which, A Dance with Dragons, took him five years to write and was finally published in 2011. Martin is still at work on the sixth volume, The Winds of Winter, which is not expected to be published until 2015 at the earliest, which is when Season 5 of Game of Thrones will premiere.

In June 2013, Martin told Entertainment Weekly he didn't think the chances of Game of Thrones catching up with the books were likely. "I don't think they're going to catch up with me," he said. "If they do, we'll have some interesting discussions." But in a recent interview with Vanity Fair, he changed his tune a bit. "They are. Yes. It's alarming," Martin said when asked if the race is on. "I'm hopeful that I can not let them catch up with me."