Louis Theroux travels to Idaho to spend time with people preparing for the collapse of society, from stockpiled bunkers to armed communes. He visits Safetrek, a survival-supplies store stocked for a coming breakdown, and Almost Heaven, a mountain community built as a refuge from the government and the 'New World Order' its residents believe is coming. He sits with families building straw-bale houses by hand, meets self-described patriots and military enthusiasts, and visits the Aryan Nation Church, letting its members explain their worldview without much pushback. A recurring surprise is how many of these survivalists started out as hippies or environmentalists, distrustful of mainstream society from the opposite political direction before arriving at the same bunkers. Theroux's usual method holds: mild, curious questions that let people talk themselves into revealing exactly what they believe and why, whether that is imminent nuclear war, economic collapse, or a government coming to disarm them. The episode stays close to individual households rather than zooming out to politics or history, watching how the fear plays out in daily choices.