With the clock ticking on how long the Family can remain in the dangerous city, Tom leads a desperate attempt to find Abby. With Abby still missing and Greg recovering from his injuries, the Family are left scavenging for survival in the city. While Naj leaves graffiti messages for Abby, Tom steals supplies from other survivors. The Family learn that more people have been abducted like Abby, and that the kidnappers bear the markings of a known pharmaceutical company. As Tom leads Al, Anya and Sarah off on this trail, Greg and Naj find themselves confronted by the group Tom stole from. In the Lab itself, Abby is re-infected by Whitaker, who will stop at nothing to find his miracle vaccine. Jill Whitaker (wife of James), desperate to know the truth about what is going on, escapes from the area of the facility she has been restricted to and discovers Abby. Abby explains to her that everyone is dead, including the government, and that she is being deliberately reinfected with the virus as part of the search for a cure. Unable to cope with the news, Jill releases Abby who goes on to escape from the building. Jill is arrested by the guards and put under quarantine. James Whitaker struggles to maintain his authority over his rebellious stuff who are infuriated by the news he has hidden his family in the laboratory. He advises the sinister Mr Landry (his boss) about the loss of Abby and is ordered by him to ensure she is returned promptly.