Walder Frey and Roose Bolton reveal their alliance with the Lannisters, leading to a slaughter of the Stark party.
This episode marks the final appearances of Robb Stark (Richard Madden), his pregnant wife Talisa Stark (Oona Chaplin), and his mother Catelyn Stark (Michelle Fairley).
After the bedding ceremony begins, the doors are locked and the band starts playing "The Rains of Castamere," a song about Lannister ruthlessness.