Aborigines in Australia, woodchucks in Pennsylvania, the Nobel Prize in Stockholm and the gay community in New York—what could possibily link such disparate elements? The answer is Hepatitis. NOVA examines this elusive disease, what causes it, how it is spread and how you get rid of it.

NOVA explores the science of natural engineering and asks the basic questions: what makes a good design in nature and why did a particular plant or animal adopt a particular design?