Bill Kurtis journeys to the northern tip of Brazil where ethnobotanist Mark Plotkin studies among the Trio Indians. A Trio healer takes Dr. Plotkin and Kurtis deep into the Amazon rain forest and reveals which plants have medicinal uses. The search for knowledge continues at the National Cancer Institute near Washington, D.C., where thousands of previously unknown plant species, collected by ethnobotanists, are tested as possible cures for cancer and AIDS. Also includes "Flight for Survival" investigates the habits and habitats of the American Bald Eagle, including methods used to bring it back from near extinction.