The Battle of Winterfell is over, and the zombie threat to Westeros has been cleared, leaving room for Game of Thrones to return to political intrigue... and leaving fans wondering if Sansa Stark might be doing some serious plotting against the Dragon Queen.
It's been clear since the first moment that Jon brought Dany to Winterfell that Sansa is none too pleased about the fact that her brother bent the knee, and her interactions with Daenerys since then have been incredible. Sansa has repeatedly thrown shade (and had some thrown back), and made a point of her dislike and distrust of Daenerys to Jon. She's also become a serious political player in recent seasons, so could Sansa already have betrayed Daenerys?
"The Last Of The Starks" ended with a shock, as Euron attacked Daenerys' fleet on their way to Dragonstone, killed Rhaegal, and took Missandei captive - only for Cersei to behead her in the final scenes. That Cersei would be attempting to lie in wait for Daenerys and take her down before she could reach King's Landing makes sense... but it's possible that Cersei had a little help, in the form of a tip-off from Sansa.
Euron's sneak attack on the Targaryen fleet and her dragons is exactly the kind of shocking twist that Game of Thrones fans love. Everything seemed to be balancing out, a new plan was in place... of course something was going to go horribly wrong. However, it is a little surprising that Euron and Cersei were able to hit them quite so hard, and quite so fast. Daenerys' return to Dragonstone was certainly somewhat likely, and it's already been established that Cersei has been planning to take down dragons with her scorpions for quite some time (since she was seen using the first of these giant crossbows on a dragon skull).
However, would she have simply left Euron's ships floating near Dragonstone for weeks, waiting for the moment that they would arrive? It seems unlikely that Cersei would be happy to deploy her whole fleet just on the chance that Dany would come back to her ancestral home, and even more unlikely the Euron would want to put an end to his creepy new place in the royal bedchamber for an unknown amount of time, just to hang out in the waters and wait for dragons to fly overhead. Not to mention the fact that even in Winterfell, there was some dissent over where the armies and dragons should go, how long they should rest before taking on King's Landing, and where. If even the inner circle of Team Targaryen wasn't sure what would happen, how would Cersei have known?
This didn't seem like a scene of an army who was simply waiting just in case, but that he knew what was coming, and exactly when. If this is the case, it means that someone tipped Cersei off - and Sansa may be a likely suspect as the Judas in Winterfell.
On the face of it, it may seem unlikely that Sansa would betray her own brother in order to make a secret pact with Cersei. After all, she despises Cersei more than almost anyone else for everything that happened in King's Landing. However, she may not see it as a betrayal, but a way of protecting her family, and Jon himself. From the scene in the Godswood where Arya and Sansa learned Jon's secret, it's clear that the Stark women would be happy to double cross Daenerys to protect the North. They've destroyed the army that was a threat to them, they don't trust the Dragon Queen, and Sansa has previously asked Jon if he truly believes in her cause, or if he is simply in love with Daenerys.
Sansa may have decided that Cersei is the lesser of two evils, and that she would be able to broker a deal where Westeros is split into two kingdoms. The Starks would take the Northern half, making Jon King in the North (and Sansa effectively Wardeness of Winterfell while Jon is away doing his royal duties), and leaving the South to the Lannisters. The show has made a point of repeating the idea that Starks don't do well down South, so why would Sansa even care about keeping it? Rather than creating more bloodshed, taking out Daenerys and making a pact with Cersei would avoid another war, and allow the Starks to start rebuilding the North as their kingdom.
As well as motive, Sansa certainly had the means to let Cersei know, too. The plan to split the armies and send the dragons back to Dragonstone would take a few days to put into motion, and then the sea journey itself is significantly longer than the one from King's Landing to Dragonstone. Sansa learned the plan in plenty of time to send a raven to Cersei - especially if she had started plotting this with the Queen in advance.
Of course, there may be more going on here than a simple plan to betray Daenerys and claim the North for herself. Not only has Sansa been revealed to be one of the most cunning and cutthroat characters in the final season, but she absolutely despises Cersei, and would love to double cross her. More than that, it's been made abundantly clear that while Sansa has a certain level of respect for Cersei's cunning, and awareness of how her mind works, she absolutely does not trust her. In this season, she's already berated Tyrion for trusting his sister, so it's unlikely that she would turn around and make a pact with Cersei, believing that it would actually be fulfilled.
Instead, it's possible that Sansa is planning something much bigger - and something that would get rid of both the current Queens in Westeros. She's constantly seen having quiet conversations with Royce, and while this may be simply to hammer home the fact that the Vale is loyal to Sansa, it could also suggest that she's got something in the works. The Northern Lords are loyal to Sansa, as well as the Vale, so perhaps she is drumming up support for Jon as King, and planning to help Daenerys and Cersei take each other out so that she can put her brother on the throne and rule the North herself.
With all that said, it still seems unlikely that Sansa would pair up with Cersei... but someone else may have been the one to betray Daenerys: Tyrion Lannister. Despite his protestations that he truly believes in the Dragon Queen, it's becoming increasingly obvious that he cannot properly advise her or control her, and that she is giving in to her worst mad-Targaryen impulses. Tyrion's conversations with Varys have made it clear that he is not willing to openly admit that he no longer believes Daenerys would be a wonderful ruler, but his exhaustion with the idea of Jon as King suggests that he may actually prefer that.
He doesn't believe that Jon would be happy to wed his Aunt and rule by her side, and it may be that he (not Sansa) is the one trying to get the two Queens to destroy each other so that Jon can rule. He and Sansa may even have been plotting this together - it's been shown that since their experience together in the crypts during the Battle of Winterfell, these two have become close again, and Sansa is the one that told Tyrion about Jon's true parentage. Sansa and Tyrion would certainly make for an incredible power couple at this point, and this kind of plot may not be beyond them.
Varys is another strong possibility for the one who betrayed Daenerys to Cersei - as he always says, he puts the good of the realm above all else. This may even make more sense than Sansa or Tyrion plotting, as they are still essentially 'good' characters, while Varys seems to be wavering. However, that wouldn't explain what Sansa is plotting, and her simply sitting back in Winterfell and doing nothing is even less likely than her scheming with Cersei. With only two episodes left in the series, everything is sure to be revealed soon...
Game of Thrones continues Sunday at 9pm on HBO.