Sean Pertwee narrates this documentary exploring the passions and intrigues - from families torn asunder to jealous plots and sibling rivalries - that drive members of the world's largest wolf pack, living in Yellowstone National Park.

Spanning three states, Yellowstone is America's most famous national park, with a cast of charming inhabitants set against stunning scenery. This film follows a family of river otters through the year as they learn to fish, fend off attacking coyotes and travel great distances around the beautiful park.

Documentary reporting on an ambitious plan to reintroduce wild wolves into America's Yellowstone National Park. The animals were virtually hunted out of existence 100 years ago and this film follows one pack as they attempt to re-establish themselves in the famous mountain wilderness