Led by Sheriff Howard `Duke' Perkins and Councillor `Big Jim' Rennie, residents of Chester's Mill come to terms with the trauma and tragedy caused by their town being enclosed in a dome-like force field.

A fire in town brings home the reality of the residents' situation and tempers start to fray. Meanwhile, Joe decides to map the dome, Junior is stalking Barbie and Dodee is picking up transdome communications.

Big Jim organises a search party in the forest when rogue cop Paul escapes from custody. Junior and Julia bond in the underground tunnels, and Angie is still locked up.

A potentially deadly outbreak of meningitis breaks out. Meanwhile, Julia questions Phil about her husband's whereabouts.

The Chester's Mill residents are delighted when the military return with coachloads of their loved ones. Only Barbie suspects that it is not the altruistic gesture that it seems.

Riots erupt when the main water supply pipe of Chester's Mill is destroyed and the townsfolk begin to fight for the remaining resources. As another resident meets a violent end, Julia and Dodee try to track down the source of a high-pitched screech.