A dramatic change in the Russian crab industry rocks global markets and drives new competition between Dutch Harbor captains and their Russian adversaries. As crab prices skyrocket legendary captains return to claim their piece of a historic payday.

A typhoon slams the Saga forcing Jake and Johnathan to make joint decisions. Sig races against the storm to make the first offload. Rapid repairs land the Cornelia Marie in the eye of the storm. Captain Phil's charts lead Josh and Casey into treacherous seas.

Still reeling from deadly typhoon Hagibis, the fleet claws its way back into competition against the Russians. The pressure to make up ground has mounted and it's do-or-die for the captains, even if it means danger or even war.

With the Russian menace looming, co-captains Johnathan and Jake blast a shotgun at their problems while a vicious fist fight breaks out on the Seabrooke. Meanwhile, Wild Bill blows an engine and Mandy bets on science to get back on crabs.

The Cornelia Marie uses US satellites to spy on the Russians, Scott pioneers a dormant fishery and Wild Bill faces off with a Russian greenhorn.

It's all hands on deck to finish King season strong. Johnathan goes under the knife at sea. Junior bets it all while chasing the elusive Golden King crab. Wild Bill goes toe-to-toe with an unruly greenhorn.

Junior risks crossing into Russian waters to tank golden crab. Co-captains Jake and Johnathan attempt an alliance with longtime rival Keith Colburn. Josh Harris bets his season on instinct. Short on quota and options, Wild Bill seeks work in Russia.

As winter slams the fleet, the Coast Guard responds to a mayday call while captains and crew brace for the loss of friends; the clock is ticking on the cod derby for Wild Bill and Junior; Sig and Monte track an Opilio hoard at the Russian line.

As the crab biomass migrates across the Russian line, Josh and Casey dump 175 pots on the border. Sig and Mandy go dark ship in towering seas. Jake's new deckhand gets injured while Junior attempts to steam through False Pass in a nighttime blizzard.

Facing a 500-mile wide Siberian storm, Josh takes a big risk to keep the Cornelia Marie crew safe. Junior loses control of his rudders putting his boat at the mercy of heavy seas. Jake's greenhorn problems get a lot worse when one clogs the toilet.

Listing heavily and taking on water, Junior calls on chase boat rescue for the first time in series history. Wild Bill sends Nick 20 feet off the deck in spite of his fear of heights. Josh and Casey hit a massive wave that knocks out greenhorn Maria.

On the Summer Bay there's hell to pay when Bill's backup block goes missing. Cornelia Marie skippers Josh and Casey navigate a tenuous partnership at the Russian line. Weighed down by three full tanks, Sig puts a heavy Northwestern in Mandy's hands.

The Wizard catches fire in a unhappy storm known as a bomb cyclone. Josh and Casey attempt to fish in 30-foot seas, while two rogue waves slam the Southern Wind. Wild Bill grinds his crew 72 straight hours bringing himself to the brink of collapse.

Battling exhaustion, Wild Bill and his crew face the full wrath of the bomb cyclone. A snapped tendon puts the Summer Bay down a man. Josh gambles on crab-rich grounds in a costly venture north. An injured Mac fights to get Junior through the storm.

As an injury knocks Sig out of his wheelhouse, Mandy takes the helm to face a disgruntled Northwestern crew; on the Wizard, damaged hydraulics and an umbilical hernia deal Keith a double gut punch; Josh and Casey suffer tragedy on the Cornelia Marie.

Stuffed pots come at a price as Jake scrambles to repair a slack tank before ithugs his crab or capsizes the Saga. Josh and Casey's rudder fails in heavy traffic and Wild Bill's new greenhorn makes an easy target for an out-of-control picking hook.

Josh and Casey race to haul pots as engine failure threatens their delivery window. As seawater destroys his hydraulic motors, Junior attempts a risky high seas delivery of three new motors. Harley and his crew bang heads over his fishing strategy.

Sig and Mandy conspire to get Jake to do their prospecting, but the former deckhand seizes the moment to fill his own tanks. The Wizard crew must break through ice to rush Keith to a doctor. Junior fears the worst as a deckhand falls from the stack.

A rare weather event churns up rogue waves as supermoon tides collide with a cyclonic snowstorm. Josh and Casey face a 55-foot monster, while Jake risks capsizing to repair his rudder in unruly seas. Monte's big move north pays off in massive pots.

As the super snow-moon storm peaks, the Cornelia Marie's deck becomes a gauntlet for Josh and Casey's greenest greenhorn. Ice fog overtakes the fleet as Monte scrambles to stay afloat, Harley loses an engine and Junior fights a sea-flea infestation.

As the fleet mounts a final Winter season push, sad news rattles the Cornelia Marie wheelhouse. Lady Alaska greenhorn, Gabby, overcomes a painful injury to support her crew. Wild Bill's deckhands must devise a bush fix or face hauling pots by hand.

Saga loses a veteran deckhand, forcing Jake to steam a greenhorn army to the Russian line. Amid scuttlebutt that ports are closing due to a virus, Josh fights to get home for a reunion with his brother and Sig's daughter gets rushed to the hospital.

The Cornelia crew fights to save its gear from sea ice; Jake risks the far north to fill his tanks before his son's birth; amid news of a looming pandemic, Russian boats mysteriously disappear and captains race to dock before crab prices crash.