At the Twins, Arya, disguised as Walder Frey, poisons the remaining lords of House Frey. The White Walkers march toward the Wall, and Edd receives Bran and Meera at Castle Black. Organizing the defense of the North at Winterfell, Jon accepts the loyalty of Houses Umber and Karstark over Sansa's objections, their previous leaders having supported Ramsay. Trying to even the odds, Cersei demands that the North bend the knee, and hears Euron's proposal of marriage in exchange for his Iron Fleet and an opportunity to kill Theon and Yara; she declines over his untrustworthiness, and he promises to return with a gift that will prove his loyalty.
Jaime tells Cersei they crucially need allies. At the Citadel, Samwell "borrows" restricted library books and learns there is a large deposit of dragonglass at Dragonstone, sending word to Jon; he also finds Jorah, now heavily infected with greyscale, quarantined in a cell. In the Riverlands, Arya meets some friendly Lannister soldiers and "jokingly" claims she will kill Cersei, while the Hound begins to believe in the Lord of Light after Thoros shows him a fiery vision of the Wall and the Army of the Dead. Daenerys comes home, arriving at Dragonstone, House Targaryen's ancestral seat, with her army and large dragons.