Plot: 'Heroin Crisis' - America is facing the worst drug epidemic this country has ever seen: more people are dying from overdoses than from car accidents-and at the center of it is an explosion in the use of heroin. Thomas Morton traces the causes and impacts of the crisis, from the poppy farms of Mexico to the hills of West Virginia, and investigates how users, first responders, and government officials are responding to the new reality of American drug use