Obesity in America has stopped being a cosmetic complaint and become a structural one, and this episode, the third of four in HBO's The Weight of the Nation series, looks at why the numbers stay so stubborn. About a third of American adults are obese and another third overweight, and the film treats that plateau as a scientific and social problem rather than a matter of willpower. Researchers describe how eating behaviors laid down in early childhood shape adult weight, tracing obesity's roots to biology and psychology together rather than to personal failing alone. The camera moves into neighborhoods where the built environment does much of the damage: streets without safe parks, corner stores without affordable fresh food, communities where the healthy choice simply is not the easy one. Doctors and public health researchers lay out the downstream costs, more serious disease, more chronic pain, billions in lost productivity and higher insurance premiums for businesses and families alike. The episode's case is that obesity is engineered by environment as much as chosen by individuals.