Heart of Gold

A young girl named Myskina Olga finds herself hunted at once by the World Government and by a treasure hunter calling himself Mad Treasure, since she alone can point the way to the Pure Gold, a metal rich enough to buy the whole planet. Fleeing onto the Thousand Sunny, Olga steers the crew toward Alchemi, a vanished island sealed within a colossal footballfish that she calls Bonbori. Once she and Luffy are cut off from the others, she admits to having lived for two hundred years and to bitterly resenting her father, whose creation of the Pure Gold lured pirates, killed her mother, and left them swallowed by the beast. Because Tsutomu Kuroiwa scripted both works, the special threads directly into Film: Gold and even introduces that movie's antagonist, Gild Tesoro.

Pushing his way inside the fish, Mad Treasure seizes Olga together with Nami, Usopp, Robin, and Chopper, pressing them into forced labor. Luffy, by contrast, joins forces with Myskina Acier, the girl's long-lost father, a survivor who endured among the creature's lingering dinosaurs, and the two set out with Zoro and Sanji to break the captives loose. Treasure herds his prisoners deep into a trap-riddled mine guarding the Pure Gold, past arrow snares, an organ Olga unlocks by singing the song her mother taught her, and a crushing keyhole puzzle. Acier reveals he forged the metal to slow the spread of Olga's lethal South Blue Emperor Fever, hoping she would last until a cure appeared. He blows the mine apart to entomb the gold and Treasure, yet Treasure claws free and snatches the prize, only for Luffy to beat him while Zoro and Sanji drop the lieutenants Naomi Drunk and Psycho P. Father and daughter make peace, and Chopper afterward cures her with medicine he devised inside Bonbori.

Tatsuya Nagamine directed the special, which premiered on July 16, 2016. The crew's clothing and their fresh Vivre Card pointing to Gran Tesoro situate the story ahead of the smartphone tie-in titled Gold Episode 0. Taking place after Dressrosa, it shows Usopp's early grasp of Observation Haki and lets Chopper enter Arm Point without swallowing a Rumble Ball. After the metal is wholly drawn into Bonbori's glowing lure and the fish slips back into the New World, the Straw Hats comfort themselves with the Gran Tesoro invitation Nami pinched from Treasure. A final scene confirms Tesoro engineered the entire chase.