Examine the paradox of whales, penguins, iguanas and dolphins that inherited a burdensome legacy from their land-dwelling ancestors: they must breathe in open air. Visit the Galapagos Islands, where evolution still experiments with life's ebb and flow between land and sea. Off the South American coast, witnesses an orca whale family teach their young the art of beaching to hunt sea lions. On the Antarctic ice, emperor penguins care for their land-locked baby chicks.

Hitch a ride on the ocean's superhighways as giants of the deep ride the currents in perpetual search of their next meal. Get uncomfortably close to the world's largest animal, the massive blue whale, with a heart as large as a small car, a tongue as heavy as an elephant and a tail as wide as an airplane wing. Witness the grace and precision of a great white shark attack. Swim with yellowfin tuna and jump through the waters with spinning dolphins.

Explore the living, breathing, colorful mountains of coral that shelter an extraordinarily diverse group of species of every color, shape and behavior. See how these living gardens protect the egg of a tiny zebra shark, and how a hermit crab latches onto venomous anemone for protection. The coral even offer a peaceful lagoon for the mother whale and her newborn calf.

The sandy plains of the seabed can appear empty, but they actually hide multitudes of bizarre creatures, including masters of camouflage that disappear into the sands, fish that walk across the ocean floor and fish that appear to dance on their heads while hunting prey. Other marine life must hit the beaches to survive. Witness the epic journey that a leatherback turtle faces, dragging its 1,000-pound body to the top of the beach to lay its eggs.