The season started so strong for Arya Stark. She wiped out the Frey army in one fell poisoned-wine swoop. Then, after multiple years away, she finally returned home to Winterfell. That’s where the problems began. (Actually, the problems began with Ed Sheeran, but let’s pretend that never happened.)
Now, Arya doesn’t recognize the new Sansa; Sansa doesn’t recognize the new Arya; and Petyr Baelish, who planted a letter that Sansa was forced to write while in Lannister custody, has them pitted against each other. Also, Arya’s “Go Bag” is filled with floppy faces, her brother’s the Three-Eyed Raven (happens), and the only time she’s happy is when she’s sparring with Brienne. Heading into Sunday’s Game of Thrones finale, things have never been more tense between the Stark girls. It’s all coming together for Littlefinger… or is it?
It’s important to remember that Arya is a trained assassin, a master manipulator, someone who can literally look like anyone, while Sansa knows better than to trust a man who craves power after her time spent with Joffrey and Ramsay; she also learned from the best, Cersei, when it comes to deceit.
It’s hard to believe they’re being conned by that dope Littlefinger. Sansa herself even said, “Only a fool would trust Littlefinger,” and, “He’s not a generous man. He wouldn’t give you anything unless he thought he was getting something back.” There’s also the symbolic gesture of Bran, who can see into the future, giving Littlefinger’s Valyrian steel dagger to Arya, as if to say, “You’re going to use this on someone who isn’t your sister.” His actions speak louder than words, which is good, because he’s not saying much.
The evidence is stacked towards Arya (and Sansa, but mostly Arya) pulling a con job on Littlefinger. She wants him to see her snooping around. Plus, as Redditor ScienceMuddafucka (as reliable a source as any) theorizes, “In what seems to be the most psychotic Arya scene, Arya basically threatens to cut off Sansa’s face and pretend to be her. The entire scene is Arya playing the Game of Faces, presenting lies as truths. She even says that they are playing.”
She plays this game when she tells Sansa that she remembers Sansa standing on Ned’s execution stage – Sansa fought and screamed, and Arya knows this. Arya played the game when she told Sansa she would never serve the Lannisters – Arya served as Tywin’s cupbearer. Arya tells Sansa she wonders what it would be like to wear her face and her pretty dresses, to be Lady of Winterfell – we are beaten over the head since [season one] that Arya HAS NEVER WANTED ANY OF THESE THINGS. Arya is playing the game of faces, and when she realizes Sansa hasn’t caught on to her lies, she hands her Littlefinger’s dagger, symbolically saying, “I trust you and want you to protect yourself from Littlefinger’s lies.” (Via)