"It's the end of the world as we know it (and I feel fine)," sang R.E.M.'s Michael Stipe, and it's a proclamation that must resonate with the people profiled in this series. That's because they are all preparing for doomsday, whether it's caused by a natural disaster, a financial collapse or a nuclear winter, and their plan is to outlast and outlive any apocalyptic scenario. The series goes inside America's "prepping" subculture and introduces otherwise ordinary folks who are stockpiling food, water, weapons and whatever else they think is necessary in the event basic services should falter and society turns chaotic and violent. Also, each prepper's plan is reviewed by the consulting firm Practical Preppers, which analyzes its potential effectiveness in case the prepper's worst fears become reality.