As a storm brews in the mountains, the people of Jackson Hole prepare for the worst amid increased sightings of Infected. Meanwhile, Abby weighs her options.

In 2018, Seattle FEDRA confronts an unexpected foe. Ten years later, Ellie and Dina find themselves in the middle of a bloody battle between the zealous Seraphites and a ruthless militia.

As the Wolves and the Scars prepare for a battle that could potentially end their longstanding feud, Ellie's search draws her away from her friends and toward a devastating confrontation.