Disc 1: "Sweet fresh water:" Explores the Amazon River, the world's largest river system, from its source in the Peruvian Andes to its huge coastal delta in Brazil. Great waterfalls, such as the Angel Falls in Venezuela and Iguassu in Brazil, demonstrate the power of rivers to shape the landscape. "Jungle:" Host David Attenborough makes a vertical journey down a Kapok tree, whose crown emerges above the jungle canopy. He descends by ropes through various layers to the forest floor below, finding en route some of the most colorful and extraordinary plants and animals on earth. "Open ocean:" Looks at the vast amount of space covered by the earth's oceans, underwater topography, the minute, drifting plankton and forests of kelp, food chains, and the evolution of fish and mammals.
Disc 2: "Northern forests:" Explores the adaptations that trees make to enable them to survive long, cold winters. He shows how animals depend upon the trees for leaves, cones, and bark. "Seas of grass:" Grass grows all over the world, sustaining a host of creatures, particularly the African grasslands, which are home to the greatest collection of savannah animals. Here, antelope, zebra and wildebeest reside with their predators, lions and cheetahs. "Frozen world:" Visits icy mountain slopes in the Andes and travels to the remote Arctic and Antarctic to explore how various plants and animals have adapted to these frigid, forbidding conditions.
Disc 3: "Margins of the land:" Talks about the animals and plants that make their homes in the shifting world of mud and sand in tidal areas. "Sky above:" Describes the atmosphere as a covering to the earth that is constantly on the move with currents of air manufacturing the world's weather. He shows that in order to drift and fly, plants and animals must overcome gravity, but at the same time, the world would be a chaotic, weightless place without gravity. "Baking deserts:" Describes how desert animals survive heat and drought in a variety of ingenious ways.
Disc 4: "Worlds apart:" Despite their often small size and isolation, many islands are inhabited by wildlife. Explores Aldabra Island in the Indian Ocean to visit giant tortoises that have reached their zenith in a hostile landscape of jagged coral rock where survival may mean eating your neighbor. "Buildings of the earth:" Reveals how huge forces formed the earth, how continents move, and how the planet earth has become so amazingly varied. He visits an erupting volcano in Iceland, finds giant plants on Mount Kenya, and investigates the recolonization of Krakatoa and Mount St. Helens by wildlife. "New worlds:" Looks at the mixed fortunes of a wide variety of animals that have been affected by man's damage or changes to the environment. He also examines the fortunes of man himself and his impact through time on the earth. Also provides a glimpse into the possible future of the earth .