With time running out, the freight crew struggle to make their delivery to a salvage crew stranded in the wilderness and Jim James returns from town with a huge surprise for his wife Nancy.

A homesteader races to airlift his stranded snow machine out of the frozen tundra; disaster strikes when a couple spends their first winter alone in the wilderness.

A couple must move their cabin away from a rapidly rising river; a leaky roof must be replaced before a storm; an avalanche threatens to derail a freight train.

Jim and Nancy rush to make repairs before the cold Alaskan winter chases them out of their home. Off gridder Dan Mawhinney decides to sell his cabin, but first he must find a buyer. On the railroad, delays threaten to put the train behind schedule.

A family faces down a threat to its food supply; a man makes a grueling 5-hour hike in the wilderness; an ice storm threatens to derail a scheduled freight train.

A porcupine infestation threatens to leave Nancy and Jim without electricity. Dave Weems' city-living nieces hunt for their own supper. On the railroad, an emergency crew battles blocked bridges to make way for a shipment of valuable military equipment.

A magnitude-4.2 earthquake threatens to bring the railroad to a standstill and derail a speeding freight train. Steve and Cassie Brosius race to build an emergency shelter to protect their young baby. Dave Weems’ nieces visit to sample life in Alaska.

When temperatures rise and breakup hits Alaska, a new set of problems threaten lives on and off the rails. Jim and Nancy journey to an abandoned cabin and discover that a bear has taken up residence. Cathy and Larry are in search of an emergency vehicle.

As spring arrives, people scramble to repair their cabins and homesteads; the freight team prepares for a cargo of explosives.

A five-hour, real-time train ride through Alaska's frozen wilderness provides the sights and sounds, mile by mile, of an epic journey through America's Last Frontier.