NOVA profiles two very different scientists: Richard Feynman, a theoretical physicist, at the pinnacle of his career—a Nobel prizewinner; and Richard Lewontin, a biologist and highly regarded population geneticist from Harvard University.

High in the Hoggar Mountains, in the exact center of the Sahara desert, lives Sidi Mohammed and his family: children, grandchildren, cousins and a few former slave women. Their environment, one of the most ungenerous on earth, provides them with almost nothing. NOVA examines the changing lifestyle of Sidi Mohammed.