Perhaps overshadowed in all the incest and zombie dragons of Game of Thrones’ finale were the Stark siblings pulling a fast one on Littlefinger. The revelation of Arya and Sansa’s deception caught a few off guard, but stars and director Jeremy Podeswa now explain how a missing Bran scene set the whole thing in motion.

You’re warned of full spoilers for Game of Thrones Season 7 from here on out, but one thing “The Dragon and the Wolf” didn’t take time to explain was the extent of Arya and Sansa’s collaboration to execute Littlefinger. We’d seen the two sisters uneasy with one another all season, though clearly something happened off-screen to facilitate their con with help from Bran’s greenseeing.

As Jeremy Podeswa explained to The Daily Beast, most of Sansa and Arya’s season-long feud was genuine, though he isn’t certain exactly when Bran stepped in:

I really believe that some of Littlefinger’s manipulations of Sansa were working on her, and that there was a question in her mind at some point of what Arya’s motives really were and whether she could trust her. And I think there was a feeling from Arya that Sansa saw herself as Lady of Winterfell and that she didn’t deserve to have that title. Littlefinger’s strength is that he finds things that are real and finds a way to manipulate the situation around those things. And so I do think that there is a germ of truth in all of that. Personally, I don’t think that they were putting on this ruse for the entire season. I feel like what probably happened is that Bran got involved and he was able to answer a lot of questions and fill in a lot of gaps the both of them had, and later when we see him in the scene with Littlefinger, all the stuff that Bran is saying in that scene is not news to Sansa and Arya. So clearly they’ve been apprised of all this stuff before. But exactly when that happened is the question. Like how early did they know all this and how early did they decide to turn the tables on Littlefinger? That’s a bit of a question.

Off-screen explanations are one thing, but Isaac Hempstead-Wright himself tells Variety that an actual scene had Sansa visiting Bran for exactly that purpose, and didn’t make the final edit:

We actually did a scene that clearly got cut, a short scene with Sansa where she knocks on Bran’s door and says, ‘I need your help,’ or something along those lines. So basically, as far as I know, the story was that it suddenly occurred to Sansa that she had a huge CCTV department at her discretion and it might be a good idea to check with him first before she guts her own sister. So she goes to Bran, and Bran tells her everything she needs to know, and she’s like, ‘Oh, s---.’

Podeswa may have been playing coy with his knowledge of deleted scenes, though Hempstead-Wright doesn’t specify exactly which episode the moment was intended for. Either way, the Stark sibling drama at Winterfell largely took a backseat to Season 7’s main arc, and writers clearly had options for how best to arrange the big reveal.

We’ll have more on Game of Thrones Season 7 and beyond in the coming days, so stay tuned. Did you figure out Sansa, Arya and Bran’s big trap ahead of time?