The captains set out to catch the first fish of the tuna season in the Series 4 premiere.

A careless prank leads to a feud between two of the veteran captains.

A mechanical issue keeps TJ from fishing and he must rely on his brother's skills to get the boat up and running again.

It's week four of the North Atlantic bluefin tuna season and Captain Paul Hebert fights for his first tuna of the season. After days of nothing to show but pulled hooks and sharks, tension mounts on the Kelly Ann. Captain Greg Chorebanian and first mate Greg Gibbs of the harpoon boat Kristiana steam into Gloucester on a mission: to kick rival Captain Hollywood's butt. But they're at a disadvantage without a pilot to guide them to the tuna like Hollywood has. Yet, Hollywood's pilot, Mark Brochu, can't help him throw the harpoon and land a fish.

It's week five of Gloucester's bluefin tuna fishing season, and when a sudden storm engulfs the fleet, each captain must decide if the risk of staying out on the water is worth the reward of catching more bluefin tuna. For Captain TJ Ott, of Hot Tuna, the storm is unwelcome as he pushes to maintain his lead over Captain Dave Carraro, of FV-Tuna.com, and Tyler McLaughlin, of Pin Wheel. Meanwhile, Captain Dave Marciano, of Hard Merchandise, and Paul Hebert, of Kelly Ann, look to salvage their seasons before they find themselves out of contention and money.

It's week six, and Pin Wheel has a narrow lead over last season's champion fishing vessel Tuna.com, while Hot Tuna, Hard Merchandise and Kelly Ann are lagging behind. Now, Captain Paul Cheney and his crew are about to enter the scene and shake things up, with the smallest boat in the fleet — the fishing vessel Drama. They have a lot of catching up to do, with six weeks of the fishing season gone and no tuna. Meanwhile, the crew of the FV-Tuna.com will have to start their trip without a captain, and Dave Marciano gets frustrated as Hard Merchandise keeps hooking and losing bluefin. With each vessel struggling to put meat on the deck, anyone could end up on top this week.

It's week seven of the North Atlantic Bluefin tuna fishing season and the Gloucester captains must decide to make the long steam to where the fish are biting or take their chances fishing closer to shore. Captain Tyler McLaughlin of the Pin Wheel lands the biggest fish of the season in waters off of Maine and the other captains head north to cash in on his hot spot. When Captain T.J. Ott of the Hot Tuna sets up on his former deckhand Tyler's spot, it's a boat-to-boat face-off for who can put meat on the deck.

It's week eight of the Atlantic bluefin tuna season, and as the season ticks past the halfway point, the Gloucester captains are determined to work harder than ever to put tuna on their decks and charge into the rest of the season as strong as possible. But being on the water for the past two months is taking a toll on crew members and one mate faces a dilemma — keep fishing or quit so he can spend more time with his wife and kids. Last season's champion, Captain Dave Carraro of FV-tuna.com, charges into the week atop the leaderboard, but by only a slim margin. If Dave's biggest rival, Captain Tyler McLaughlin of Pin Wheel, lands a fish this week, it could bump Dave out of the coveted first place, so Dave and his mates Sandro and Geordie are not taking any chances and are fishing as hard as ever.

It's week nine of the North Atlantic bluefin tuna season, and Captain Paul Hebert of the troubled Kelly Ann struggles to prove his worth to his crew — and keep his job — after catching only three tuna in the first two months of fishing. Captain Tyler McLaughlin of the Pin Wheel is currently leading the fleet, but his first mate quit last week. Rival Captain Dave Carraro of FV-Tuna.com is determined to capitalize on the loss and get back into the top spot. Meanwhile, Captain Dave Marciano of Hard Merchandise is eager to take advantage of his last week with his son Joe on the boat. They'll try to catch more than one fish to establish themselves as one of the top boats in the fleet.

It's the beginning of week 10 of the North Atlantic bluefin tuna season in Gloucester, Massachusetts. With only six weeks of fishing left, the competition is heating up, driving captains to push themselves and their crews to the brink. On Kelly Ann, the future of Captain Paul Hebert's tuna season hangs in the balance, and on Pin Wheel, Captain Tyler McLaughlin's aggressive behavior may cost him his one remaining mate. The FV-Tuna.com crew fights to hold on to their No. 1 position on the leaderboard, and on Hard Merchandise, after hooking a shark, Captain Dave Marciano must dive under the boat to fix a problem. Meanwhile, beleaguered boat Drama is so far in the red that this week is their final chance to catch their first bluefin; otherwise, they'll have to call their season quits.

It's week 11 of the North Atlantic bluefin tuna season, and bad luck, bait problems and big egos plague the Gloucester fleet. With only five weeks of fishing left before the season closes, hardworking Captain Dave Marciano of Hard Merchandise has defied popular belief by rising to the top of the leaderboard for the first time this season. Last year's champion, Captain Dave Carraro of FV-Tuna.com, is determined to regain the top spot, but an epic week of catching by another boat may threaten that goal. Meanwhile, Captain Tyler McLaughlin of Pin Wheel has a lot of work to do to mend his relationship with his one and only crewmember, Travis Brown, after shoving him to the deck the week before.

It's week 12 of the North Atlantic bluefin tuna season and, after catching no fish last week, last season's champion Captain Dave Carraro, of FV-Tuna.com, has sought help from his ally, Captain TJ Ott, of Hot Tuna. TJ directed Dave to the spot where he just caught three tuna and now Dave is desperate to capitalize on the information. TJ expects that, in return, Dave will alert him if the fish are still biting in his hot spot, but Dave hasn't earned the nickname "Tricky Dave" for nothing. Will Dave put fishing ahead of friendship and fracture ties with an important ally?

It's week 13 of the North Atlantic bluefin tuna season, and with only three weeks left to fish and the No. 1 position on the line, every Gloucester captain is desperate to stack the deck with bluefin and earn some final paychecks before the season closes. Last season's top-earning captain, Dave Carraro of FV-Tuna.com, is leading the fleet, and he and his crew are determined to stop at nothing to repeat last year's success. But Dave's treatment of other boats in the fleet has not earned him any friends this season, and the other captains each have a few reasons to beat him. With the end in sight, it's the closest race in Wicked Tuna history and a new frontrunner threatens to emerge with each bluefin caught.

It's week 14 of the bluefin tuna season and with less than two weeks of fishing left, the top four crews are locked in a tight race to be Gloucester's best bluefin boat. Though Captain Dave Marciano of Hard Merchandise has the slowest and most rundown boat, he and nephew Jay Muenzner are currently leading the fleet. But with huge paychecks and pride on the line, Captains Dave Carraro of FV-Tuna.com, TJ Ott of Hot Tuna and Tyler McLaughlin of Pin Wheel won't go down without a fight.

It's the final week of the season and Hard Merchandise holds a narrow lead over the fleet with fifteen fish. Hard Merchandise's closest rivals FV–Tuna.com, Pin Wheel, and Hot Tuna are all within striking distance of the lead and when a single tuna can be worth upwards of $20,000 the battle for the top spot will go down to the final day. Will Marciano be able to hold onto his lead? Will Dot Com reclaim their title for the second year in a row? Will Paul Hebert make enough money to be able to support his family through the winter? Will Tyler reclaim former glory or will TJ win the title for the first time?

Just one or two fish is all that separates the top four boats as the crews enter the final five days before the Atlantic bluefin tuna season in Gloucester, Massachusetts closes and the competition comes down to the very last day as the boats scramble to land more fish.