A girl named Myskina Olga is pursued by both the World Government and a man named Mad Treasure, as she is the only one who knows the location of the Pure Gold, a substance that can buy the entire world. Olga ends up sailing with the Straw Hat Pirates, and they journey to find the Pure Gold on the lost island of Alchemi, which is located inside the stomach of a large anglerfish named Bonbori. Olga and Luffy get separated from the others, and Olga reveals that she has lived for 200 years, and has a grudge against her father for making the Pure Gold, which led to the death of their mother and them being eaten by Bonbori.
Mad Treasure and his crew enter Bonbori, and capture Olga, Nami, Usopp, Robin, and Chopper, forcing them to be slaves. Meanwhile, Luffy forms an alliance with Olga's father Myskina Acier, and they, Zoro, and Sanji go to rescue their captured allies. Mad Treasure takes his prisoners into a mine where the Pure Gold is located, but Luffy and Acier intervene as the Straw Hats and Olga find the Pure Gold. Olga then discovers that Acier created the Pure Gold to prevent the onset of an illness and save her life, and the pirates are forced outside as Acier destroys the mine. Mad Treasure gets his hands on the Pure Gold, and Luffy battles him as Olga and Acier reconcile. Luffy beats Mad Treasure, and Zoro and Sanji beat Treasure's subordinates Naomi Drunk and Psycho P before they escape from Bonbori. The Pure Gold is fully absorbed by Bonbori, but everyone is fine as Olga and Acier resume their normal lives and the Straw Hats get a Vivre Card that leads to Gran Tesoro.
A Marine fleet is escorting a girl who is snacking on candies given to her though complains about wanting meat. She also schemes to try to find a way to escape her captors (though talks so loud that they can hear her). However the ships are suddenly attacked by a nearby pirate ship under the command of Mad Treasure, a ruthless treasure hunter who ate the Jara Jara no Mi. His subordinates, Naomi Drunk, a archer who gets her aim while drunk and fires explosives and Psycho P, a swordsman who ate the Iro Iro no Mi and can camouflage himself via spray cans, make quick work of the Marines before Treasure boards the lead ship. He finds the girl, Myskina Olga being guarded by a masked CP0 agent who engages in battle with him. Olga makes a run for it and is seemingly cornered by Treasure's crew. But calls her pet dinosaur, Elizabeth, who can run on water, to save her. Treasure does not stop her as he knows she will lead him to the Pure Gold. After the raid, he talks with Tanaka, an associate of Gild Tesoro, who wishes to hire him to find the Pure Gold and will pay him whatever he wishes. Treasure states he doesn't really care for treasure, but loves the thrill of finding it and accepts Gild's job. Tanaka gives him an invitation with a Vivre Card in it to Gran Tesoro to lead Treasure to the location once he succeeds.
Meanwhile, Olga is making her way through the ocean, directionless and hungry until spotting a ship in the distance which turns out to be the Thousand Sunny. Spotting the Straw Hats fishing and deeming them weak based on Luffy's looks, she makes her way to them feigning weakness till she is pulled aboard by the crew before trying to take Luffy hostage and demanding food for his release. However the attempt fails when the crew don't show any worry for Luffy and he gets along with Elizabeth. Sanji feeds her regardless seeing how weak she is and the Straw Hats introduce themselves to her. Robin manages to identify Olga being from Alchemi by the pattern on her dress and reveals to the others that it is a lost island that was rumored to have birthed the Pure Gold, gold said to be more brighter and more valuable then a ton of regular gold. This interests the crew and when Olga state she can lead them to it, they are more then willing to take her up on it (despite overhearing that Olga would likely betray them first chance she got).
However, Mad Treasure's crew manages to catch up to Olga and the Sunny with Treasure demanding they hand her over. When Olga refuses to go with him, he sends his crew after her though the Straw Hats manage to fight them off. Treasure uses his Chain Chain powers to grab Olga and tries to pull him to his ship but the Straw Hats pull her back resulting in a tug of war. Zoro eventually cuts her free, but the ring she had on her finger flies off in the process, revealing it had Pure Gold in it, and lands in the ocean. This in turn summons a angler fish Sea King which Olga dubs as Bonbonri. Bonbonri sucks up the ring and proceeds to do the same to the two ships. As the Straw Hats make to escape however, Olga reveals that the Pure Gold is within Bonbonri's stomach and they must venture inside him if they want it. The Straw Hats comply and head into the Sea King with Mad Treasure following suit, ramming the side of the Sunny to get them to crash into Bonbonri's uvula. Luffy manages to save the ship but is knocked into stomach acid in the process. Olga goes to save him with Elizabeth while the rest of the Straw Hats and Mad Treasure's crew drop into Bonbori's stomach.
Luffy awakens to find himself on an island which Olga reveals is one of three that Bonbori has eaten and are all located within his stomachs with the third her home, Alchemi, being where Pure Heart is located. It is soon revealed that dinosaurs have survived within the island and a few try to eat them but Luffy manages to beat one and scare off the others. As they eat the dinosaur that was felled, Olga reveals that she is 200 years old much to Luffy's shock. She goes on to explain that back then her father had created the Pure Gold which attracted pirates to her family with her mother being killed as a result. She blamed her father for it and was going to throw the ring from earlier into the ocean to spite him when Bonbonri appeared and swallowed half the island with her and father along with it. She assumes her father died as she's the only survivor of Alchemi. She has since stayed in the stomach for 200 years until one day was accidentally spat out. She was soon found out by Marines and captured by the CP0. She agrees to show Luffy the way out as long as they do as she says. Luffy agrees and they handshake on it.
However, they are interrupted by the arrival of Mad Treasure who has managed to find them. Both Luffy and he fight and are evenly matched. However, Treasure then reveals that he had managed to capture Usopp, Nami, Chopper, Robin, and Brook. Luffy tries to charge and attack Mad Treasure, but he suddenly grabs Nami by using his chains and threatens to torture and kill her and the others by using his chain powers, forcing Luffy to surrender to keep her and the rest of the crew from getting hurt. Treasure binds him up and demands Olga to help him, she agrees but only on the condition that the Straw Hats are not harmed. He agrees though leaves Luffy to be dissolved by the tides of Bonbonri's acid. After they leave, a dinosaur come back and pick up Luffy in its mouth intending to feed him to his young. He manages to get the dinosaur to spit him out and scares off the younglings, however there turns out to be a rather chubby human in a costume among them. He frees Luffy and explains that he was swallowed with his island 200 years ago and survived by blending in with the dinosaurs and eating the meat fed to the young. However when Luffy reveals that Olga's story was similar to his, the man reveals himself to be her father, Acier Myskina, and more then thankful to hear that she's alive. With that, the two return to the beach and get the assistance of a dinosaur similar to Elizabeth, this one named Chavez, to cross the acid juices.
Meanwhile the captured Straw Hats are forced to row Treasure's ship in the lower decks. As they do, Nami reveals that she is familiar with Treasure as, before she met Luffy, she had tried to steal from Treasure's vault but a ran into a competitor who had gotten there first. They were both found and captured by Treasure but said competitor used Nami as a decoy and never came back for her. Olga takes that as a sign to never trust friends, but Nami states that she later found friends she could trust and that Olga should believe in Luffy. As that goes on, Luffy and Acier make their way to second stomach but have to stop when the acid there proves too much for Chavez to cross, luckily they find the Thousand Sunny. They're suddenly attacked by a few of Treasure's men lead by Psycho P. Despite using his powers to camouflage the men, Luffy manages to beat them and force Psycho P to retreat. Back with Treasure, they finally reach Alchemi and the temple where Pure Gold is held but likewise find a sign from Acier that warns them that those seeking the gold will be met with death. This is soon confirmed when one of Treasure's men comes out with an arrow in his back, signalling that the temple is booby trapped.
The group press on and soon come across the first trap, a organ that will shoot out arrows if the song given is not played correctly. Brook, being a musician, volunteers to take the challenge but cannot play the final notes as the last page is faded out. Robin and Chopper defend him from the arrows as he tries to figure out the last notes. Olga, seeing the trust between the crewmates in such a deadly situation, comes to their aid and sings a song taught to her by her mother as it is the same one need to be played on the organ. With this, the group is able to bypass the trap and continue onward. As they head on, Psycho P arrives and informs Treasure of Luffy's survival, lifting the morale of his crewmates and Olga. Treasure leaves Psycho P and Naomi to guard the entrances as the group continues on. Back at the Sunny, Luffy finds Zoro and Sanji who had gone off to get materials for the Sunny as well as Franky who was on the ship fixing the damage done to it and converting it to survive the acid juices. With the Monster Trio united, Luffy, Zoro, Sanji and Acier head off to catch up with the others. Meanwhile Treasure's group have reached another trap that involving trying to open a drawbridge while avoiding the dinosaurs guarding the area. Usopp manages to use his sniping skills to drop the drawbridge while Chopper keeping the dinosaurs at bay.
Luffy's group soon reach the temple but are attacked by Treasure's men, Zoro and Sanji stay behind to fight Naomi and Psycho P respectfully while Luffy and Acier run on ahead. As they do, Treasure's group have arrived at the last trap which involves keyholes and needing to find the right one to open it with the key provided. Nami goes for the task but finds that when she picks a wrong one, the dummy keyhole shocks her and and brings down the upper portion of the alligator shaped structure on her with the intent to crush it victim. Usopp, Brook and Chopper try to hold it up as she continues, but it gets heavier with each wrong keyhole. Eventually, Nami faints from too many shocks forcing Olga to try and continue in her place. However she too can't find the right one and it seems all of them will be crushed. Luckily, Luffy arrives and saves them by smashing the upper part of the alligator structure before angrily confronting Treasure. Acier soon catches up and sees is daughter for the first time in two centuries. He tells her to leave with the Straw Hats before opening a trap down underneath them and dropping them into a hidden area. Going forward, they find it's Acier's lab and within, the Pure Heart in a container. Robin finds a journal explaining that he had made the Pure Heart along with his wife to save his daughter as she had contracted a disease that will kill her as she grow older. The light of the Pure Heart however could slow a person's growth, so he cut off a piece and put it into a ring before giving it to Olga with the hope that she will survive long enough for a cure to be found. Olga soon realizes that her father does care for her and that he likewise was sadden over her mother's death, calling herself a fool for holding a grudge against him for so long.
Above them, Acier reveals to Mad Treasure that he had implanted explosions around the temple and goes to activate it, intending to sacrifice himself to bury the Pure Gold and Mad Treasure along with it. Luffy's group feel the explosions going off and escape the area before the blast engulfs it. However Treasure likewise manage to survive, though saved Acier in the process, and land in front of the Pure Gold, claiming it for himself. Olga rushes to her father and reconciles with him while Luffy goes to confront Treasure. The two begin to battle trading blows and insights on what it means to hunt treasure. Luffy wanting to share the adventure and wealth with his friends while Treasure believes he only needs people as "tools" to achieve his hunts. Eventually, Luffy manages to break through Treasure's chain defenses and sends him flying into into Bonbonri's stomach lining. While at the same time, both Zoro and Sanji easily win their fights as well. Everyone boards the Thousand Sunny as the acid juice begin to back up due to Bonbonri's upset stomach and ride the current out. While Treasure's crew plea with him to board his ship, but his obsession with the Pure Gold results in him getting swallowed up by the juices just as he grabs it.
The Thousand Sunny manages to escape from Bonbonri back into the New World. As they do, they see Bonbonri's antenna light glowing bright with Pure Gold which Acier explains is from the Pure Gold that he's eaten since he was attracted to the metal. But now that there is no more Pure Gold, it is unlikely he'll ever surface and thus unlikely that they will see Alchemi again either as Bonbonri sails off into the distance. The Straw Hats soon reach a nearby island and drop Acier, Olga, Elizabeth and Chavez off. Though the parting seems bittersweet as without the ring with the Pure Gold, Olga's disease will eventually spread and kill her. However when Acier reveals that Olga's disease is called the South Blue Emperor Fever, Chopper reveals that there actually was a cure for it having been developed during the duo's time within Bonbori. Chopper gives it to Olga (via needle shot much to Olga's dread as she hates needles) before the crew part ways with the two to allow them to live out their new lives.
While happy that they helped the father and daughter, the Straw Hats lament they did not get anything out of the adventure. That is until Nami reveals she swiped the invitation to Gran Tesero off of Mad Treasure. Seeing it as a great consolation prize, the crew make their way to the cruise liner.
In the credits, we see that Acier and Olga opening up a lab on the island. Acier soon developed a medicine that reduces weight and got his slim figure back. He soon sold it and made much money from the endeavor to which afterward he treated Olga to all the meat she could eat, with her no longer having to fend for herself to get it. While within Bonbori, Treasure (having survived the acid at the loss of the Pure Gold), Psycho P and Naomi are still stuck within him and eat dinosaur meat together. After the credits, we see the masked CP0 member report back to his commanding officer about the loss of Olga and thus the Pure Gold. The officer decides it is for the best that it is lost since it keeps the world's balance in check. The two both correctly assumed that Tesoro was the one behind Treasure's involvement.
At Gran Tesoro, Tanaka reports of Mad Treasure's failure to obtain the Pure Gold to Tesoro. Tesoro brushes it off however and decides to find something to "entertain" himself with his vast fortune while the woman from Nami's flashback sits at his side as he laughs.
Characters in Order of Appearance
- Although a stand-alone story, this special leads into One Piece Film: Gold, with both the special and film written by Tsutomu Kuroiwa. Mad Treasure appeared in One Piece Film: Gold, and Film: Gold main antagonist, Gild Tesoro, appeared in this special.
- This special features an element from the previous film, with Naomi Drunk's usage of small Dyna Stones in her attacks.
- The time of this special is sometime after the Dressrosa Arc as Nami has the Straw Hat Pirates' new bounty posters, and Usopp's novice usage of Kenbunshoku Haki.
- Chopper uses Arm Point, despite no longer using it as one of his transformations after the timeskip. It is shown that like most of his other post time-skip transformations he doesn't need to eat a Rumble Ball to transform.
- During the final fight, Sanji battles Psycho P, the swordsman of the antagonist group. This is the second time Sanji fought the antagonist swordsman, the first being Heaby in the third movie.
- Luffy's final fight against Mad Treasure is the second time Luffy uses Gear Second and Gear Third simultaneously, with the first time being against Gecko Moria after Oars' defeat.
- The song sung by Olga's mother was later reused in the anime as an instrumental version in Episode 838.
|Boss Luffy Historical Special|
|Chopper Man Special|