Our mastery of cold is something we take for granted, whether it s air conditioning and frozen food or the liquefied gases and superconductivity at the heart of cutting-edge technology. But what is cold? How do you achieve it, and how cold can it get? This two-part NOVA special brings the history of this frosty fascination to life with brilliant dramatic recreations of high moments in low-temperature research and the quest for ever-lower notches on the thermometer.

The first hour, The Conquest of Cold, opens in the 1600s when the nature of cold and heat was a complete mystery. Were they different aspects of the same phenomenon? The experiments that settled these questions helped stoke the Industrial Revolution.

Our mastery of cold is something we take for granted, whether it s air conditioning and frozen food or the liquefied gases and superconductivity at the heart of cutting-edge technology. But what is cold? How do you achieve it, and how cold can it get? This two-part NOVA special brings the history of this frosty fascination to life with brilliant dramatic recreations of high moments in low-temperature research and the quest for ever-lower notches on the thermometer.

In the second hour, The Race For Absolute Zero dramatizes the titanic rivalry between Scottish researcher James Dewar and Dutch physicist Heike Onnes, who plunged cold science to the forbidding realm at which oxygen and then nitrogen turn into liquids. The race continues today as scientists pioneer super-fast computing near absolute zero the ultimate chill of -459.67° F where atoms slow to a virtual standstill.

At age 78, E.O. Wilson is still going through his "little savage" phase of boyhood exploration of the natural world. In "Lord of the Ants," NOVA profiles this soft-spoken Southerner and Harvard professor, who is an acclaimed advocate for ants, biological diversity, and the controversial extension of Darwinian ideas to human society.

Actor and environmentalist Harrison Ford narrates this engaging portrait of a ceaselessly active scientist and eloquent writer, who has accumulated two Pulitzer Prizes among his many other honors. Says fellow naturalist David Attenborough: "He will go down as the man who opened the eyes of millions 'round the world to the glories, the values, the importance of—to use his term—biodiversity."

Thousands of ancient footprints stretch for miles across New Mexico’s White Sands National Park, capturing moments when Ice Age humans encountered now-extinct beasts, including mammoths and enormous ground sloths. These footprints tell an intimate story about what life was like during the Ice Age and reveal surprising new evidence about when humans arrived in North America.