"Move as millions. Survive as one." That's the catchphrase of this seven-part event for which a National Geographic team spent two-plus years recording across 20 countries and all seven continents. Narrated by Alec Baldwin, it tells the stories of many of the planet's species and the journeys they undertake to ensure their survival. The diverse range of animals shown -- many revealing behaviors never caught on film before -- include Botswana zebras, Mali elephants, flying foxes in Australia, Pacific white sharks, and the white-eared kob of the Sudan, thought to have been destroyed during decades of violence.