Ed and Jean Jackson survived the early days of the apocalypse with the help of their close friends, Chief Barnes and Kathy McGinley. Over the years since the infection began, they chose to step back from the battle against the infected dead and remain within the safety of the shelter hidden in Green Cavern. Now, they have embarked on a perilous mission of their own to attempt the rescue of a group of survivors who are clinging to life near Niagara Falls and the Finger Lakes of New York.