After having realized she could never truly be No One, Arya reclaimed Needle and left the House of Black and White. Upon her defection, the Waif (Faye Marsay) immediately ran to Jaqen (Tom Wlaschiha) and begged for permission to finally kill Arya, to which Jaqen agreed on one condition: that she not let Arya suffer.
Arya then did a costume change and bought passage on a ship to Westeros. However, before she could leave Braavos, an old woman snuck up behind her, stabbed her in the gut, and twisted the knife. It's revealed that the old woman is the Waif in disguise (duh), but before she could finish the job, Arya jumped into the canal. She somehow managed to get herself back to shore and stumbled down the street, visibly shaken and paranoid that every face she saw was actually the Waif.
Despite the fact that we've seen stab wounds similar to the ones Arya suffered already kill her brother Jon and her sister-in-law Talisa, we can say with near certainty that Arya is not going to die. She's far too great a character to be killed off in such a bizarre and anti-climactic fashion before her storyline could come to a natural conclusion. The trailer for Sunday's episode also shows her running around Braavosi rooftops, so clearly she isn't injured too badly, let alone dead, when the show picks back up.
So what actually happened with Arya? Here are the most popular — albeit insane — theories, explained.
The Fight Club Theory: Some fans suggest that Arya and the Waif are not actually nemeses, but the same person, with the Waif being the Tyler Durden to Arya's Edward Norton. The meat of this theory is that the Waif and Arya represent her two possible paths - becoming No One and embracing her born identity - and that all the fights between Arya and the Waif are her inner struggles literalized. That would make the Waif's attack on Arya a (failed) last-ditch effort to kill her emotions and officially become No One.
To outsiders, this fight would have looked something like this:
However, given the absurdity of this theory and the fact that the Waif is equally emotional as Arya, it doesn't quite line up.
The Gone Girl Theory: Arya's scenes with Lady Crane were so good that many believe the actress actually helped Arya fake her own death. Some theorists posit that Lady Crane set Arya up with a medieval squib, such as a pouch of pig's blood over her stomach, so that the Waif would think she had injured Arya more than she had. Then Arya could lead the Waif to the dark room where Needle awaits, giving Arya the fighting advantage thanks to her former blindness.
But there's a big hole in this theory, which assumes Lady Crane's work in the theater makes her an expert on special effects. Let's just take a minute to reflect on how Lady Crane's play faked injuries:
Yeah, I seriously doubt Lady Crane knows how to make a convincing squib.
The Face/Off Theory: It's also been suggested that maybe the Arya we saw get stabbed isn't Arya at all, pointing to her costume change and the absence of Needle as proof. Giving this theory more credence is the fact that at one point in the scene, we see the back of a girl who appears to be wearing Arya's costume from a previous episode walking towards the Arya we see get stabbed.
But for this theory to be true, Arya would have to have given her face to someone else to wear. But unlike Melisandre's (Carice van Houten) glamour powers, which changes her appearance through magic, the House of Black and White seemingly can only use faces of the dead by physically cutting them off the corpse.
So unless Game of Thrones either retcons how the House of Black and White functions or decides to give Arya magical glamour abilities, it doesn't seem reasonable that she could have given her face to another person.
The Mrs. Doubtfire Theory: Although Arya only learned how to change faces by literally wearing someone else's face, Jaqen H'ghar may not be restricted by the same rules.
Jaqen is far better versed in the powers of the Faceless Men, and the first time we ever see him change faces, he appears to do so using magic. (That is, unless he had been carrying a face around in his pocket during his entire time at Harrenhal.) Interestingly enough, Jaqen also references serving the "Red God" in Season 2, which is the god from which Melisandre derives her glamour powers.
If this is the case, Jaqen - who has always had a soft spot for Arya - may have assumed her identity to spy on the Waif and see if she fulfills her promise to not let Arya suffer, a test she ultimately fails.
The notion of Jaqen testing the Waif also makes sense since the Waif's whole vendetta against Arya seems to be based on Arya's inability to let go of her personal vendettas. And yet, what is the Waif's hatred of Arya but a personal vendetta?
If the Waif is no better than Arya at being No One, it's not outside the realm of reason to imagine Jaqen secretly spying on - and potentially killing - the Waif, because, as he previously warned, "One way or another, a face will be added to the wall."
This theory would also provide an excellent payoff for all the behind-the-scenes drama of the Braavosi play. Much like Arya and the Waif, Lady Crane and Bianca work together in a profession that forces them to become other people, with the latter bearing a deadly grudge against the former. At the end of the Crane-Bianca feud, Arya steps in and saves Lady Crane, declaring, "Careful of that one. She wants you dead." At this point, the camera begins shifting focus between the Waif and Bianca, as each faces down their potential target.
If the Lady Crane-Bianca feud was foreshadowing what would happen between Arya and the Waif, Jaqen could easily take on the savior role by assuming Arya's identity and therefore stopping the Waif's vengeance mission from succeeding.
To be honest, all of these theories are nuts. But this is a show that has ice zombies, time-travel and warging, so nothing is impossible. What do you think happened to Arya?
Game of Thrones airs Sundays at 9/8c on HBO.