Feature-length version of the BBC/Discovery TV series "Planet Earth," which was originally released theatrically in Europe and Japan. The first theatrical release from DisneyNature, it follows the migration of a trio of animal families: polar bears, elephants, and humpback whales using cutting-edge photographic technology, which allowed filming from great distances so as not to disturb the subjects. Fothergill and Linfield worked for five years on the project, including 250 days of aerial photography, at some 200 locations in 64 countries.