Jake returns to his hometown of Jericho after being away for several years in order to collect on money his grandfather left for him. As the citizens of Jericho question Jake on the past five years, he remains secretive about his whereabouts. When Jake leaves for San Diego, he sees a nuclear explosion occur off in the distance, which marks the moment everyone's lives instantly change forever. With the aftermath of the nuclear explosion looming over them, the people of Jericho become paranoid about one another, resulting in hidden agendas and guarded secrets to be revealed. But in the terror of it all, some are able to find inner strength they never knew they had.