[Warning: this story contains spoilers for the season seven premiere of HBO's Game of Thrones, "Dragonstone."]

Heading into season seven, all eyes were aimed at a House Stark family reunion. But how many people were considering the ramifications of a House Frey family reunion?

Red Wedding retribution was already on the menu last season, as Lord Walder Frey (David Bradley) suffered an unglamorous and lonely death at the hands of Arya Stark (Maisie Williams) in the season six finale. But Arya's Red Wedding revenge tour didn't end there. Game of Thrones returned this year with an opening sequence that serves as a final answer to the show's most brutal and iconic sequence, an instant all-timer of a scene that's sure to go down as one of the most satisfying moments in Thrones lore, due in large part to its surprising book connections.

The episode, called "Dragonstone," begins in the great hall of the Twins, the same spot where the Starks were slaughtered. A very much alive Lord Frey sneers down at his gathered family members, all of whom are drinking and eating and otherwise causing a ruckus. Frey loudly taps his table twice in order to get his fellows' attention, a move that harkens back to how the original Red Wedding launched.

"You're wondering why I brought you all here," says Frey. "After all, we've just had a feast. Since when does Old Walder give us two feasts in a single fortnight?"

The old man reveals that he's "gathered every Frey who means a damn thing so I can tell you my plans for this great house now that winter has come," and in a certain reading of those words, he's not lying. But first, a toast. Frey makes all of the gathered members of the family drink a glass of Arbor Gold, a highly valued white wine grown in the south of Westeros. "Proper wine for proper heroes," he bellows. 

When they set down their cups, Frey praises his family as "the men who helped me slaughter the Starks at the Red Wedding." They cheer uproariously, and Frey quickly quiets them down, greatly changing the temperature in the room.

"Yes, yes... cheer. Brave men, all of you," he snarls. "Butchered a woman, pregnant with a baby. Cut the throat of a mother of five. Slaughtered your guests after inviting them into your home."

Frey's vivid description of how Talia (Oona Chaplin) and Catelyn (Michelle Fairley) died sends a chill through the room. Soon, the chill is replaced with choking, as the various Freys begin gagging and gasping for air.

"But you didn't slaughter every one of the Starks," Frey continues. "No, no, no. That was your mistake. You should have ripped them all out, root and stem. Leave one wolf alive, and the sheep are never safe."

Within seconds, every single Frey hits the floor, dead or rapidly dying from drinking poisoned wine. Frey then reveals he's not Frey at all, as he rips off his own face and reveals the true killer beneath: Arya. She turns to the lone survivor — Walder's youngest and latest wife — and tells her to deliver a message to the crown.

"Tell them the North remembers," says Arya. "Tell them winter came for House Frey."

Helen Sloan/HBO

And with that that, the episode cuts to the main title sequence, just enough time to process the gravity of Arya's actions. When the season seven premiere screened in Los Angeles last week, audience members burst out in uncomfortable laughter and cries of excitement throughout the twisting-and-turning scene, and it's easy to understand why: in an instant, Arya singlehandedly wiped out House Frey, one of the two central families responsible for the most vicious and most memorable mass murder in Game of Thrones. There are still people in Westeros who played a role in the Red Wedding, but in terms of sheer percentages, Arya just carved out a huge portion of the perpetrators. "Winter is here," indeed.

House Frey's fall is an exciting prospect on a number of levels, not the least of which is that it blends a couple of key storylines from George R.R. Martin's A Song of Ice and Fire series on which Thrones is based. In the books, there are two major players seeking active vengeance for the Red Wedding. The first is Lord Wyman Manderly of White Harbor, the head of a great Northern house who lost a son during the Red Wedding. He's since played a politically clean game with the Lannisters, Boltons and Freys, cooking up revenge in secret — literally cooking, too, as he has members of House Frey killed, baked into pies, and served up as delicious pastries to their unknowing relatives. 

"The best pie you have ever tasted, my lords," Manderly tells the Freys at one point in A Dance with Dragons. "Wash it down with Arbor Gold and savor every bite. I know I shall."

In season six's finale, Arya served Walder Frey a slice of Frey pie before slitting his throat. Now, as of the season seven premiere, Arya completed the Manderly sequence by poisoning the Frey family with Arbor Gold. Given that it's a white wine, and given that winter is here, perhaps it's worth referring to the Red Wedding response as the White Wedding? Certainly comes with a catchy theme song.

Beyond Manderly, Arya is channeling another character from Martin's novels: Lady Stoneheart, the resurrected form of Catelyn Stark. In the books, the Brotherhood Without Banners discovers Catelyn's corpse three days after the Red Wedding. Beric Dondarrion (Richard Dormer) sacrifices his final life in order to revive Catelyn, but the person who returns is not the person who died at the Twins. Taking on the moniker of "Lady Stoneheart," the monstrous Catelyn takes over the Brotherhood and rededicates their mission: rather than helping out small folk, they will instead focus all efforts on wiping out every single living Frey in the Riverlands, as well as anyone with even the slightest affiliation to the Red Wedding. 

Lady Stoneheart even hangs Brienne of Tarth (Gwendoline Christie) and Podrick Payne (Daniel Portman) at the end of the fourth book, A Feast for Crows. She demands that they find Jaime Lannister (Nikolaj Coster-Waldau) and bring him back for retribution, but Brienne refuses, at least initially. The events of the fifth book heavily suggest that Brienne has had a change of heart, and is now on the verge of putting Jaime on Lady Stoneheart's vengeful path.

Of course, this version of Catelyn Stark never arrived on the show, and at this point, she never will. Her debut was initially expected at the end of season three, then again at the end of season four, and when it didn't happen at the end of season five, most fans agreed it would never happen at all. Recently, Martin confirmed the show has no Lady Stoneheart plans; it's likely that Game of Thrones showrunners David Benioff and Dan Weiss wanted to save its big resurrection surprise for Jon Snow (Kit Harington) conquering death in season six. (We now believe Beric's role in Stoneheart's creation could factor into a major Jon moment later this season.)

While Game of Thrones deprived book readers of Lady Stoneheart and Wyman Manderly, both of those beloved characters and their insatiable desire to avenge the Red Wedding live on through the unexpected yet completely worthy avatar of Arya Stark. The North remembers both Stoneheart and Manderly, but even without them, and with Arya in place, winter is very much here. 

Now, how much further will Arya's vengeance tour take her? Will she bring the blizzard all the way down to King's Landing, as she tells the Lannister soldiers in this episode? Will she decide that it's time for a proper family reunion, and instead head north toward her siblings at Winterfell? Only six more episodes this year and twelve installments overall left to find out.

Watch the video below for more on the great battles still to come.

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