When Nami catches a fatal illness, the crew is forced to stop at Drum Island, a kingless country that is trying to establish a new government. Due to the actions of the previous king, Wapol, there is only one doctor left—a "witch" named Kureha who lives at the top of a mountain. Luffy and Sanji must reach the peak, but the exiled King Wapol returns to reclaim his country.
With their culinary concerns in good hands, the Straw Hats set off in search of Nami - who's on a collision course with a deadly foe!
Zoro is captured by Fishman Arlong and learns a shocking secret about Nami. Unable to believe his ears, he puts the navigator to the ultimate test.
Luffy and his crew make their way towards Arlong Park and a showdown with its fishy proprietor. Along the way, they discover a treasure map that raises more questions about Nami.
A fierce argument over where Nami's loyalties lie divides the Straw Hat Pirates and only one thing's for sure - no one is willing to risk their life for a traitor.
Nami's adopted sister, Nojiko arrives to fill in some details about the skilled mapmaker's younger days.
Nojiko continues the story of Nami's younger days. Back in the present, Nami gets agonizingly close to a long time goal, but betrayal looms on the horizon.
Nezumi comes to confiscate Nami's treasure, but who's he working for? More importantly, who's Nami working for, and what's she gonna do with her booty?
The Straw Hats' faith in Nami is restored, and now it's time for a battle royal! Luffy and the gang are determined to make Arlong pay for mistreating their friend.
The Straw Hats and Arlong's fishmen are locked in a swashbuckling slugfest, but things take a bad turn when Luffy gets trapped beneath the waves.
While his friends work to free the captain of the Straw Hats, cowardly Usopp finds himself in a position to shed his yellow streak and make his father proud.
Nami must decide between letting Arlong maintain his hold over her, or joining the Straw Hats and leading the oppressed villagers against the tyrant fishman.
Arlong better watch his back-fins, because Captain Luffy knows about all the horrible things he did to Nami - and it makes his blood boil?
Something about Nami's former prison gives Luffy an added burst of strength. He's so moved by her terrible past that he vows to destroy all of Arlong Park!
After a grueling fight, Luffy defeats Arlong and succeeds in destroying his headquarters. The merry marauders enjoy the fruits of victory while Nami makes peace with her turbulent past.
Finally, the day has arrived where Luffy's face is on an authentic wanted poster! Now there are enemies in hot pursuit as the crew makes waves for Logue Town - final resting place of Gold Roger!
Buggy gets marooned on an island inhabited by unusual creatures and tangles with the island's caretaker, Gaimon. If he is to finally destroy Luffy, Buggy must cast his lot with a mysterious woman.
The Buggy Pirates fight each other for the right to take their lost captain's place. While they're busy beating each other's brains out, a cannibalistic tribe makes plans to have something special for dinner.