Cover Page: From the Decks of the World Vol. 4 - "Shells Town - A waitress in training at a Marine Base, Rika".

Rika trains as a waitress in the Shells Town Marine base. Luffy's new wanted poster is seen posted on the side of a counter.

Luffy, Megalo, and Shirahoshi continue their journey towards the Sea Forest. Meanwhile, Hody Jones and Vander Decken IX arrive at Ryugu Palace. The whereabouts of Robin, Franky, and the Thousand Sunny are revealed.

The chapter starts with people in Coral Hill looking up at a group of figures in the sky while someone is trying to contact the Ryugu Palace on a Den Den Mushi. Luffy sees the figures as well, though he is too far away to see them clearly. It turns out that the border patrol was the group trying to contact the palace. Someone remarks how odd it is, wondering if the Den Den Mushi at the palace might be sick. The border patrol reports that dangerous individuals have entered the Fish-Man District and they just wanted the people at the palace to know that, going on to say that they do not look like normal tourists but hopefully will not cause trouble. The group in the sky turns out to be Hody Jones, Vander Decken IX, and their crews. The pirates are spread out among several of the sea monsters that the Straw Hats saw when they first arrived.

Hody announces that today marks the mental union for Fish-Man Island. If fish-men and merfolk are not of one mind, they cannot accomplish anything. Also, the humans who cannot breathe underwater should be controlled by the fish-men. Today, the fish-men's history of repeating mistakes will be resolved. Decken adds that today would also mark the anniversary of his and Shirahoshi's wedding engagement. He adds that there is no need to rush, as they can have the ceremony tomorrow. Dosun adds that Jinbe and his crew aren't on the island anymore. Zeo counts how many people in the Neptune Army pose actual threats. He comes up with four: Ryuboshi, Fukaboshi, Manboshi, and Neptune. Ikaros Much adds that if they can take out the four of them, the rest should be easy. Jones calls for everyone to begin suppressing their assigned areas. As the sea monsters all head off in different directions, Jones says that today will be the last day of the Ryugu Kingdom and they will be the new rulers of the seafloor.

The scene changes to a fish bus stop, where several defeated guards are lying on the ground, one of them saying they must tell Neptune she escaped. The woman in question turns out to be Nico Robin. She has learned that there is a Poneglyph in the Sea Forest and is on her way to investigate it. She believes that that Poneglyph contains important information about the Void Century. Back at the palace, Zoro is yelling at the Minister of the Left, telling him not to make it sound like Zoro enjoyed fighting all the pirates. The Minister of the Left says that Zoro looked very energetic during the battle and that he is a born killer. Zoro then sarcastically asks if the minister wanted to have tea be brought to the attacking pirates. The Minister of the Left agreed, saying that it would be a good idea to bring the attacking pirates tea and then talk to them. Zoro tells that his plan would not work on these people. The minister tells him that beating all pirates would not help them understand their purpose for infiltrating the palace. Zoro tells him he does not have to be that hospitable. Usopp and Nami are talking, Usopp comments that things are going in the wrong direction.

Brook wonders if Luffy already met the princess. Neptune falls over behind Usopp, his eyes full of tears. He tells them to undo his chains and to give Shirahoshi back to him. Usopp asks why they would kidnap the princess, Neptune saying that Luffy is the culprit. Brook argues that he saw Luffy and Megalo leave the room and did not see the princess with them. Neptune tells them that the princess knows not to leave the palace on her own. Also, due to how she is as big Neptune himself, there is no way she could sneak out without anyone noticing. Brook does not believe Neptune when he mentions Shirahoshi's size, as he is picturing the princess to be as bulky as Neptune with a similar build.

Neptune suddenly gets an idea, Megalo could have hidden Shirahoshi in his mouth and he could have gotten her out of the palace that way. This causes all of the tied up guards to start laughing. They tell Neptune not to make them laugh at a time like this, and even if someone thought it up, there would be no way anyone would do it as it sounds too bizarre. Nami stands up for Luffy, saying he would never kidnap anyone, and for Neptune to direct his suspicions at someone else. Neptune tells them he cannot think of any other way she could have escaped, and unless she returns safely, he will not return the other crew members or their ship. While they are arguing, one of the invading pirates, while trying to get up, rests his arm on the three levers that control the entrances to the palace and the corridor leading out of the bubble.

In the Sea Forest, someone is explaining how the area they are in is called the ship graveyard, as all the ships that get caught in currents end up there. Franky is then seen, and the man talking is seen a ways behind him. The man says that he has been researching the Sea Forest that stretches along the ocean floor. Franky says he cannot believe that he is seeing a place like the forest in the deep sea. He adds that it is the same as Fish-Man Island. The man then compliments Franky on being able to find wood from Treasure Tree Adam to build the ship. Franky tells him it is the same material that Tom used to make Gol D. Roger's ship. He adds that Thousand Sunny is also his best work. The man says that he will take care of the necessary coating, with a don. Franky thanks him and asks him his name. The man replies his name is Den.

He is a Bering wolfish merman, and Tom's younger brother. Franky asks Den why he does not resemble Tom at all, as his brother Franky figures Den should at least look a little bit like Tom. Den tells Franky he has a very human way of thinking about it, but does not blame him since families of species on land bear lot of resemblance to each other. Den explains that fish-men and merfolk can have genes that can stay dormant for generations. He gives an example, if a shark merman is born from an octopus mermaid, that would mean that at least one of the parents has an ancestor that was a shark. He goes on to say that no one on Fish-Man Island really cares what type of children the mother gives birth to.

He also adds that fish-men and merfolk cannot understand why humans have the need to categorize people. Den then asks Franky if he had a robot for an ancestor. Franky tells him he is a human. Den mentions that he received letters detailing everything about Franky and Iceburg. Franky then remembers that Kokoro used to write letters. He adds that he also knows about Tom's passing, saying that he lived with a don until the very end. Den tells Franky that if he came all the way to Fish-Man Island just to tell him, then Tom picked the right disciple, much to Franky's embarrassment as he presses his nose to make his hair stand up. Franky then remembers that he saw someone sitting a ways away and asks Den about it. Den tells him it is "boss" Jinbe, explaining that he appears to be waiting for someone, but since he is a wanted criminal he cannot enter the island.

Back at the palace, the connecting corridor is opened and the sea monsters are waiting at the main gate. The ministers recognize Vander Decken and Hody Jones, much to their shock and horror. Neptune recognizes Hody and the Minister of the Right confirms that that man is the same Hody who was once a talented soldier in the royal army. Decken is surprised, saying he was expecting to start a battle, but that everyone is already tied up. Hody comments on how he wasn't expecting such a "gift" to be waiting. He then wonders if it is a trap, saying things seems far too convenient. Zoro comments on how busy the castle is, getting one guest after another. The tied up guards plead to be given weapons. The Minister of the Left asks Usopp if they were plotting with the fish-men and if they invited them to the palace. Usopp retorts that the Straw Hat Pirates would not even be at the palace if they had not been invited. He then asks who the new pirates are.

Neptune is furious at Decken, as his presence now confirms to him that the fish-man is the real criminal and demands to have his daughter returned. Decken jokes that he had not even married the princess yet, and already the king wants her back. He tells the king he is getting ahead of himself, and calls him dad, much to Neptune's fury. He asks Decken where Shirahoshi is, saying she had better be alright. Decken is now confused, and tells the king he is acting like the princess is missing. Neptune roars at him not to play dumb, and asks why else she would not be in her room. Decken is shocked that Shirahoshi is gone.

Hody tells Decken to calm down, as the pirates he threw all landed where they were supposed to, which could mean she might still be here. He adds that regardless of whether or not she is here, he has a way of finding her. Decken realizes he is right, and uproots a large piece of tree-shaped coral, telling it to fly to Shirahoshi. After realizing it is not going toward the tower, he jumps on it, saying that after waiting for ten years, the only thing that can separate their love is death. The chapter ends with Decken saying that the princess will die in a sea of blood if she becomes someone else's.

Chapter Notes:
Rika, Ripper and Rokkaku makes their first appearance since "Diary of Koby-Meppo".
The last of the Straw Hats are seen since their separation.
Robin is heading to the Sea Forest to find a Poneglyph.
The Thousand Sunny was swept to the Sea Forest after the Straw Hats entered Fish-Man Island, where Franky is now.
Robin is heading to the Sea Forest to find a Poneglyph.
The Thousand Sunny was swept to the Sea Forest after the Straw Hats entered Fish-Man Island, where Franky is now.
Den explains why fish-men and merfolk can be completely different species even if they are in the same family, expanding upon the explanation that Pappag gave in an earlier chapter.
Jinbe cannot enter Fish-Man Island since he is a wanted criminal.
It is revealed that Hody Jones used to be a member of the Neptune Army.
This is the second time a member of the Straw Hat Pirates inadvertently helped someone invade an otherwise impenetrable location. The first being Luffy's attack on Impel Down, which the Blackbeard Pirates invaded soon after.