The crabs have vanished, which ignites a grueling hunt to save the fleet's way of life. Captain Sig returns to the helm after a major heart attack. Wild Bill debuts his own brand new boat in a crisis season. A rescue is attempted for a heart attack victim.

The fall season begins with some uncertainty. A seismic shift in sea temperature sends the fleet searching for displaced crab and then they must fight through an unseasonably large first storm.

Rising sea temperatures test the fleet. Toxic smoke engulfs the Saga. Meanwhile, Sean struggles to save the family business on the Brenna A and Wild Bill fears he could lose Nick to a terminal illness.

Wild Bill finds out the truth about Nick McGlashan's terminal illness. Jake's future is threatened by a damaging mechanical issue. Warming seas force Keith to into the unknown.

Johnathan and Andy Hillstrand fish together for the last time. Keith's inattentive crew sends the Wizard on a collision course and a belligerent deckhand tests Jake's resolve as a captain.

A massive leak fills the Time Bandit. A fistfight tests Jake's resolve while heavy winds and a snapped anchor threaten to wreck his boat. Sig's greenhorn has an awkward question.

A big decision weighs on Sig Hansen. Rookie captain Sean Dwyer gambles on a new venture with a new crew. Jake Anderson struggles to replace a lost anchor before his quota is taken away.

The last moments of the fall season bring its biggest storm. Wild Bill struggles to pilot his new boat in big seas. Johnathan faces off with a massive swell in the perilous False Pass.

Competition doubles when the quota is cut in half. Three captains arrive early for the winter season, but Johnathan goes one step further and plots a dangerous, 600-mile course to Russia.

Sig returns to the season that nearly killed him. After a tough start, Keith and son struggle to prove themselves. Wild Bill gives Nick McGlashan a second chance and Jake lets go of a friend.

When the Arctic opens up its winter wrath, the first of multiple back-to-back hurricanes descend on the fleet. Spotty fishing and mutiny also converge to create the perfect storm.

An Arctic mega-storm rocks the fleet. Sig plays cat-and-mouse with towering waves. Keith watches an 800-pound crab pot launch into a deckhand's spine. Wild Bill fights for a comeback.

Sig's stress takes a toll. Sean tries to dock in a hurricane. Keith is left dead-stick in massive seas. Jake motivates a defiant hand. Johnathan rolls the dice by Russia.

Sig, Johnathan and Jake attempt to run from a second arctic hurricane, but Keith refuses to heed the warnings. Stress-induced chest pains threaten the remainder of Sig's season.

After suffering chest pains, Sig waits in the hospital for some news. Wild Bill struggles to stay out of harm's way while also handling dissention on deck. Sean laws down the lay on Zack.

When Mother Nature stirs up the Bering Sea, Sean is set on a collision course with another boat. Two deckhands get taken down on the Wizard and Jake almost loses a deckhand...twice.

Two old friends race to finish their seasons, but one hopes to cap a storied career. Johnathan Hillstrand wants to bid farewell in a blaze of glory, but the Bering Sea may have some other plans.

The U.S. Coast Guard desperately searches for a missing crab vessel in the Bering Sea. Meanwhile, the fleet anxiously waits to discover the fate of its six man crew. Sig contemplates an early exit after a plea from his wife.

In the wake of the Destination tragedy one last storm bears down on Edgar, Bill, Sean and Jake. The Coast Guard attempts to save the crew of a fishing vessel while their boat is taking on water.