PBS | 8:00 pm

The remote Ellesmere Island, located at the northernmost edge of North America, is the setting of the new episode "Arctic Wolf Pack." Campbell Scott narrates the hour, which examines how the White Wolf survives in temperatures that can run to 40 degrees below zero, and in a lifestyle that involves being a determined and fearsome predator — often taking it far from its den — as well as a parent to the pack’s latest additions.