Contains spoilers for this episode and earlier episodes.
Arya confronts Sansa over the letter she wrote under Lannister pressure, accusing her of betraying their family. Sansa turns to Littlefinger, then sends Brienne to represent her at the planned meeting in King's Landing. Searching Arya's room, she finds the faces Arya took from the Faceless Men. Arya explains that she can impersonate people and frightens Sansa with the possibility of taking her face, but ultimately leaves her the dagger. At Dragonstone, Daenerys refuses Tyrion's attempt to discuss her succession before she wins the throne.
Beyond the Wall, an undead bear mauls Thoros. Jon's group then destroys a White Walker, causing most of its accompanying wights to collapse, and captures the one that remains standing. Its cries draw the larger army. Jon sends Gendry back to Eastwatch for help while the others shelter on an island surrounded by thin ice. Thoros dies from his wounds. When the lake freezes enough for the wights to cross, the group fights to hold them off until Daenerys arrives with her dragons.
The survivors board Drogon with their captive, but the Night King kills Viserion with an ice spear. Jon stays behind to cover the escape and is dragged into the lake. After he emerges, Benjen gives him a horse and remains to hold back the wights. Jon reaches safety and later apologizes to Daenerys for her loss. She promises to fight the dead, and he acknowledges her as his queen. Farther north, the dead pull Viserion's body from the water, and the Night King reanimates him.