Departing Dutch Harbor for Alaska's 2017 fall crab season, the fleet's veteran captains battle the deadly Bering Sea as well as their younger rivals to get their piece of a lucrative bounty. Captain Sig Hansen and his young skipper, Jake, have a massive falling out, leading to new strategies and new alliances. Josh Harris returns to captain his father's boat, and Captain Wild Bill shows rival Sean Dwyer that he's messing with the wrong captain.
As accusations fly and suspicions grow, a twisted triangle of jealousy, betrayal and revenge reveals few can be trusted on the Bering Sea. The Coast Guard races to save a crabber with a de-gloved finger. Jake strives to become an independent captain, and Captain Keith offers to take him on as an apprentice while Captain Sig plots against him.
As the King Crab become harder to find, Sean and Casey forge an alliance, but when one strikes crab, there's a possibility of betrayal. Wild Bill risks it all on a new bait and fish strategy, a dangerous mistake jeopardizes Jake's offload, and the Cornelia Marie is whipped by bad weather.
Halfway through king crab season, the Cornelia Marie is suffering from bad fishing and injuries to key deckhands that could force the boat in early. On the Northwestern, Sig goes on a daring midnight mission to shake his rivals. Back in Dutch Harbor, AK, the Wizard's captain Keith gets big news about a mystery illness from his doctor.
Captain Keith fights to keep the Wizard afloat when there's flooding in the bow, and a burst hose shuts down Jake's boat indefinitely. Sig wraps the king crab catch and gives the helm to Edgar to set his first bairdi pots, and Josh and Casey worry that their two injured deckhands won't be cleared to fish.
A massive Arctic hurricane shocks the fleet with high winds and big waves, and an unstable stack threatens to capsize the Saga. As the captains rush to pull and set pots before heading for safe harbor, Wild Bill risks driving straight into the storm to snatch his quota.
Jake makes a devil's bargain -- huge crab for hidden perils -- until his boat itself is on the line. Sig serves cold justice at sea, and Wild Bill chases a king crab jackpot. The Cornelia Marie crew learns that when you bet on a boat, the (wheel)house always wins.
On the brink of failure, Josh discovers secret fishing grounds in his late father's logbooks. A deck mishap on the Saga could end Jake's season. The Coast Guard braves pitching seas in an attempt to hoist an injured sailor from inside a ship's tank.
At the start of bairdi crab season, a spinal infection forces Keith to hand over the Wizard to his brother, Monte. Josh fights for the helm of the Cornelia Marie despite a bad showing, and major engine trouble threatens Wild Bill's season before he even makes it off the dock.
The supermoon brings the most powerful tidal surges in 150 years and sets the stage for the worst winter season. Josh and Monte chase their bounty deep into an Arctic storm, and Wild Bill hopes to get his broken boat off the dock. The rest of the fleet arrives for the start of opilio season.
A blackout leaves Jake and the Saga close to disaster in unfamiliar waters. Sig heads far above the traditional opilio grounds for the second year in a row, and Wild Bill is desperate to overcome his slow start due to engine repairs. Meanwhile, Keith makes Josh an offer only a captain could refuse.
Accidents plague the decks. Winter season rocks the fleet with 20 foot swells and 40 knot winds, and the Bering Sea takes a brutal toll on one Cornelia Marie greenhorn. In the wheelhouse, strategy is critical with crabs on the move.
Sig races to offload his tanks before losing half a million dollars in crab. The Bering Sea doubles down on punishment for one Cornelia Marie greenhorn. Tension between co-captains reaches a breaking point in the Wizard's wheelhouse.
It's baptism by fire aboard the Northwestern as Mandy takes her first shift in heavy seas. The Wizard crew battles over one crewman who isn't pulling his weight on deck, and Wild Bill changes his strategy when he's caught short on bait gear and battered by high seas.
A 150-year supermoon storm wreaks havoc on tides, churning undersea currents that rip pots right off their lines. The Coast Guard attempts a rescue mission in the heart of the storm, and Wild Bill faces his worst nightmare as a greenhorn goes overboard.
A greenhorn's life hangs in the balance as the Summer Bay crew scrambles to steal one of their own from the Bering Sea's icy grip. The Saga and the Cornelia Marie battle the colossal waves of the supermoon storm, while Mandy tackles her first haul in extreme weather.
Sig pushes Mandy to invade the Cornelia Marie's ground, sparking a battle for the crab. As the Cornelia Marie's pots get tangled with the Northwestern's, Casey takes extreme measures to defend his turf. A distress signal from the Saga sends panic across the fleet.
A severe Arctic gale batters the fleet, forcing captains to fight extreme wind and waves. The Brenna A and the Summer Bay tempt the fates and steam out of port to catch crab in the deadly winds and waves. Meanwhile, the Saga crew seeks shelter at St. Paul Island, where tidal forces snap Captain Jake Anderson's anchor.
As rogue waves threaten to capsize their boats, captains Jake Anderson and Sean Dwyer must make life-or-death decisions for their crews on deck. On the Summer Bay, Wild Bill Wichrowski faces a choice that could end his career, and Keith Colburn returns to the Wizard put an unexpected end to his brother Monte's rule.
The captains take on the steepest waves yet in an epic final surge to hit their quotas. Jake Anderson fights through a debilitating crew injury on deck of the Saga. The Cornelia Marie's Josh Harris gambles big on his crab count, and engine failure leaves Sig Hansen and the Northwestern dead in the water.