[Warning: This story contains spoilers for the fifth episode of Game of Thrones' seventh season, "Eastwatch."]

There's no surer sign that we're in the thick of the Game of Thrones end game than experiencing an episode in which the estranged Lannister brothers reunite, a long-lost character returns to the fold after three seasons away, the Mother of Dragons and the King in the North inch closer to becoming a thing, eight of the show's coolest characters come together to form a zombie snatch-and-grab squad — and the most important moment by far and away is a quick blink-and-you'll-miss-it exchange between Samwell Tarly (John Bradley) and his veritable wife Gilly (Hannah Murray).

The scene comes toward the end of "Eastwatch," as Sam vents his frustration with the maesters of the Citadel and their inflexibility on the issue of the White Walkers. In an effort to break through to Sam, Gilly brings up a passage from a book she's reading, which very casually reveals the news that the late Prince Rhaegar Targaryen annulled his marriage to Elia Martell while simultaneously marrying another woman in a secret ceremony — someone who is almost certainly Lyanna Stark, mother to Jon Snow, who is now no longer just a secret Targaryen, but a full-on legitimate one. 

Yeah. Kind of a big deal. 

Read all about the ramifications of that royal reveal here, and read on for seven other key scenes from "Eastwatch."

1. The Tarly Barbecue 

Alas, poor Dickon (Tom Hopper), who barely lived long enough to become the butt of a dirty joke. Sam's older brother, as well as his father, served as roasted-and-toasted testimony to the awesome power of Daenerys Targaryen (Emilia Clarke), incinerated in an instant by Drogon after they refused to bend the knee. Their deaths not only reinforce Dany's increasing intolerance toward her enemies, but also render Sam as the official heir to Horn Hill. Seeing as he just abandoned the notion of becoming a maester of the Citadel, will Sam instead become a great lord of Westeros? Quite possibly, assuming Westeros is still standing when Game of Thrones ends.

2. The Wine Sessions

There aren't too many major reveals in the scene between Tyrion (Peter Dinklage) and Varys (Conleth Hill), but any time we see the Imp and the Spider put their collective brains together (especially over a glass or two of wine), you know you're in for a good time. The makings for a great scene are already in place just by virtue of the two characters onscreen, but the topic of conversation — what Daenerys' volatility means for Westeros moving forward, and how it reflects her father's cruel past — makes the conversation all the more riveting.

3. The Family Reunion

Tyrion's scene with Varys isn't even his best moment of the episode. A little while later, the Hand of the Dragon Queen returns to King's Landing for the first time since he killed his father in season four, and swiftly reunites with two of the most important people in his life: Bronn of the Blackwater (Jerome Flynn) for all of three seconds, and big brother Jaime (Nikolaj Coster-Waldau) for a longer and tenser exchange. As Jaime informs his younger sibling, he once vowed to cut Tyrion in half if they ever met again. The fact that the conversation passes without any bloodshed is a big step in the right direction for both men, who just might make it out of Game of Thrones with their relationship intact — if not for the following breaking news...

4. The Lion Queen's New Cub

Over the course of the series, Jaime and Cersei (Lena Headey) have lost all three of their children in brutal fashion. Now that they're in control of King's Landing, the siblings and lovers have another shot at happiness, or at least their version of happiness: Cersei is pregnant with their fourth child, and she plans to announce to the world that Jaime is the father. Will Westeros accept their relationship? It's not like everyone in the Seven Kingdoms isn't already aware of what's going on between Jaime and Cersei, not to mention the history of incest seen throughout the Targaryen regime. But in all likelihood, these theoretical questions won't even matter, since there's no way Cersei and Jaime win the war for the Iron Throne, if there's even an Iron Throne when the series concludes.

5. The Hammer Man

He was on the show for three seasons, and then he was gone for three seasons. Now, he's back and better than ever: Gendry of Flea Bottom (Joe Dempsie), war hammer in hand and ready for action. The bastard son of Robert Baratheon (Mark Addy) makes it clear very quickly just how valuable he is in a fight, as he brings his own version of his father's signature weapon to bear upon two members of the City Watch. With Gendry back in the mix, we have someone in place who can convert all of that Dragonstone dragonglass into weapons against the White Walkers. Suddenly, this long-lost character is one of the most important figures in the story.

6. The Northern Conspiracy

What's happening in Winterfell? No, really, because it's starting to get exhausting following along with the drama in the North. In "Eastwatch," Sansa (Sophie Turner) and Arya (Maisie Williams) experience a growing divide over the Lady of Winterfell's leadership. Later, Arya sneaks into Littlefinger's (Aidan Gillen) quarters and discovers the letter Sansa wrote to her family back in season one at the Lannisters' behest — a letter Arya only discovers because Littlefinger wants her to discover it, apparently. What's his end game here? And why all the conflict between the two Stark sisters? Given everything else that's going on right now, the manufactured feud between Arya and Sansa stands out as the show's weakest plotline of the moment.

7. The Eastwatch Eight

Okay, technically it's the Eastwatch Seven, since we don't see Davos walking out into the winter wilderness with the rest of the gang. But there's a better ring to "Eastwatch Eight," isn't there? In any case, what an assortment of characters: Jon Snow, Jorah Mormont, Tormund Giantsbane, Gendry of Flea Bottom, Thoros of Myr, Beric Dondarrion and the Hound, all together, united in their commitment to face whatever bitter cold fate awaits them beyond the Wall. Has there ever been a more epic arrangement of characters in Game of Thrones history? Seems like we're saying that a lot this season, which is a very good thing indeed.

Watch the video below for the Game of Thrones cast's preview of season seven's battles.

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