Iris welcomes an enigmatic ally to their community while Hope questions the visitor's motives. A message upends the sisters' worldview, forcing them to decide between the safety of their home and the dangers of the world beyond.
The group adjusts to the reality of life beyond the walls of their community; Iris tries to take over, despite Hope's reservations; Felix and Huck follow the teenagers, while Felix is forced to face unwanted memories.
Burdened by their pasts, members of the group adopt opposing strategies for dealing with a massive obstacle; pressure is put on the group to return home.
The group seeks shelter from a storm inside an abandoned high school. While resupplying, they imagine what high school life was once like and encounter new threats both living and dead.
While the group works together to cross the Mississippi River, a plot to steer the teens back home hits a snag. A member of the group must overcome past trauma to save the others from an approaching threat.
When an unexpected newcomer reveals information that could help them reach their destination, the group cuts a deal; while some are intrigued by the new arrival, others are suspicious.
While the group searches for something to advance their quest, one of them recalls their struggles in the early days of the apocalypse. A game of truth or dare brings emotions to the surface.
A series of setbacks causes a member of the group to reevaluate their role in the mission. Someone makes a surprising discovery. A startling revelation casts everything in a new light.