In search of others in an infected world, Sam and Lily venture out in hopes to build a community of survivors as Sam struggles for his own survival after refusing to let go of his past.

In early 1900s New Zealand, Winifred and Evelyn live in their own world of love letters and romantic hiding places. When a collection of their intimate letters is discovered, Fred and Evelyn flee to safety. In a secluded new home away from threat, a deeper secret is revealed which changes the course of their lives forever.