Peter Dinklage Peter Dinklage

Game of Thrones has already broken many of its rules this season. What's one more?

Fans of HBO's epic fantasy series have been trained to expect a huge, possibly devastating game-changer in the penultimate episode of every season, followed by a more sedate 10th episode finale to deal with the aftermath. This year instead, major deaths and events have been peppered throughout Season 4, leaving its fans unsettled and unsure of what to expect. Alex Graves, who directed Sunday's finale (9/8c, HBO), promises more surprises in a 10th episode like no other.

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"The show has traditionally always made the ninth episode their big episode," he tells "This is the first season where the finale is a finale. It is an all-out, massive, episode. It's the largest episode that's every been made. A lot happens."

In fact, the episode, titled "The Children," runs 66 minutes long, perhaps to accommodate all of that action. Although some DVRs automatically adjust to this extended length, viewers are advised to double-check and adjust their settings accordingly.

While Graves keeps most details about the finale under wraps, he teases that "fans are going to find out what happens to Tyrion. They're going to see Jon Snow face-off with Mance Rayder once and for all. They're going to see many of the characters arrive at huge turning points in their stories."

From HBO's offical preview of "The Children" here, we do indeed see that Tyrion (Peter Dinklage) is awaiting his fate after being sentenced to die, Mance Rayder (Ciaran Hinds) threatening the Night's Watch, Daenerys (Emilia Clarke) dealing with her dragons, Bran (Isaac Hempstead-Wright) & Co. possibly reaching their destination, and Arya and the Hound (Maisie Williams, Rory McCann) encountering someone rather tall.

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Check back with Sunday night after the finale for our interview with Graves in which he breaks down the colossal episode. Until then, here are a few more teases. One scene he claims has "the best writing I've ever seen" and for another, he admits, "I was terrified of that scene. That was one of my toughest, of all the things I did." Also, which scene does he describe as one that showrunners David Benioff and Dan Weiss "have been waiting to make for something like a decade"?

What are your predictions for the finale? Will Tyrion be executed or will he survive? Will Jon Snow kill Mance? Who will Arya and the Hound encounter? What stresses will Dany face now? Will Bran finally find the three-eyed raven?

Game of Thrones
airs its Season 4 on Sunday at 9/8c on HBO. See why it's our editor's pick for Watch This Tonight below:

Watch This Tonight: Game of Thrones