Three years in the making, and from award-winning National Geographic cinematographers, Great Migrations is a landmark series featuring the epic struggles of animal migrations around the planet and the groundbreaking science behind these life-or-death marathons. National Geographic provides an unparalleled look at the volume and diversity of wildlife that face countless obstacles in the name of self-preservation or the survival of the species--from jellyfish and wildebeests to walruses and monarch butterflies. Filmed over 3 years in stunning high-definition. Reveals never-before-seen animal behavior. Features breakthrough filming technology. Narrated by Alec Baldwin.