It's Fall In the Arctic National Wildlife Refuge, and that means animals are on the move. Heimo pursues the tail end of the caribou migration, a bear ransacks Bob's cabin, destroying 2 years of dry meat, and the Lewis family arrives to sign of moose.

Surviving 400 miles from civilization boils down to one thing, finding food. Heimo pursues the animal that can feed he and Edna for months, a moose. The condition of Bob's boat threatens the hunt. The Seldens arrive to a flooded cabin.

Winter's wrath is nearing and to prepare for the unforgiving season when temperatures drop to -50 degrees, everyone must fight to stay alive.

Winter is here and the time for preparation is over. Bob deals with the ramifications of crashing his plane. To begin trapping, Heimo must find a way to cross a newly frozen river. Ray and his daughters set out to catch much needed meat.

The cost of life hundreds of miles from civilization, is front and center. Tyler and Ashley trek 15 miles to a lake cabin to run their dog team and search for food. Bob leaves home to see his daughter and assess the damage of his crashed plane.

Day 1 of darkness has arrived in the refuge. Heimo's golden rule to never get caught miles from home in the dark is in jeopardy. The Lewis Family prepares for a life changing event as their daughters prepare to leave and head out on their own in town.