Hidden deep in the wilderness of Alaska is the toughest town in America: McCarthy. Locked in winter's grip, the 42 souls who are brave enough to live here must battle the elements, and each other, to maintain their pioneer way of life.

The last days of winter bring change. The future of town lies in the balance. Jason races the melting river crossings to reach his crashed airplane. Jeremy tests his nine-year-old son with a risky solo dog sled run through the woods.

As seasons change in McCarthy, the town is haunted by its darkest day. The icy ground thaws into a quagmire, and old-timer Tim Mischel is marooned at his remote cabin. Neil and Jeremy's frozen truce is set on fire.

Spring means locals can finally reach the outside world to resupply. Jeremy walks a bull calf home through bear country and faces off with a hungry black bear. Jason's brother Eric departs town for a new job, leaving Jason to face the wild alone.

McCarthy is under attack from awakening bears. Jeremy's livestock is attacked and he goes on the hunt. While Gary searches for horses spooked by a grizzly.

Hidden in McCarthy is the largest man-made ruin in the world - and Neil wants to open it up to tourists. Jenny finds a secret creek that holds gold and must pack a raft to inspect the claim.