Chapter 598 is titled "2 Years Later".
After 2 years spent training on islands around the world, the Straw Hat Pirates finally reunite at Sabaody Archipelago, which is now much more lawless due to the relocation of Marine Headquarters to the New World and because of the rise of a crew of Impostor Straw Hat Pirates, who are imitating the originals and recruiting members for their own crew.
The chapter starts with Luffy leaving Rusukaina with the help of Boa Hancock. The scene then switches to Sabaody Archipelago where the locals discuss the events that happened there two years ago including the names of Supernovas who were making a name in the New World; the main topic was the reappearance of the Straw Hat Pirates who disappeared two years ago and their return at the archipelago, distributing flyers trying to recruit new members with the intention of strengthening their crew and embarking to the New World.
Meanwhile, Brook after two years has become a music superstar with the three men of the Longarm Tribe as his managers, he plans to hold his last concert tour at Sabaody stating that this will be his "finest concert ever".
While on the beach Sanji (his hair parted on the opposite side and sporting a goatee) appears and is overjoyed to see real women on the shores, after two years of training, bidding the okamas a hasty farewell as he runs off to find Nami and Robin first. At a certain bar a female with long hair in a bikini top and skinny pants talks to the bartender about the Marines changing the location of their headquarters. She witnesses the fake Straw Hat Luffy and his comrades shoot and turn away a pirate with a bounty of 55,000,000; the fake Luffy then orders more ale and wants the long haired woman to come join him as well. The locals at the bar all assume she would not refuse knowing that the pirate had a reputation yet were all surprised when she flat out refused him not once but two times. When the fake Nami went over and tried to make the woman do as they say, a stranger who suddenly appeared and sat beside the woman unleashed plant monsters that grabbed the fake Nami causing an uproar with the Fake Straw Hats with the plant tendrils wrapping around them.
The man, smiling, asks the woman if she would drink with him . She smiled back and hugged him tightly stating that he has gotten manly, revealing herself as Nami and the man as Usopp (who looks buffer than his lean build from two years ago), they make a dash out of the bar when a thundercloud appears electrocuting the pirates in the bar. Nami said that she also improved and gained some new technology. The Fake Luffy curses after them and orders his crew to find the ones responsible for going against him and kill them.
At Shakky's Bar in Grove 13, Shakky and Rayleigh were present with Sanji revealing to him that Zoro arrived first followed by Franky and that both were on the Thousand Sunny. Nami arrived third but she went out shopping due to boredom, Usopp and Chopper were fourth and fifth, Brook was sixth, arriving just before Sanji, then lastly Sanji himself. Sanji was overjoyed with the news and wondered how much Nami had changed while Rayleigh comments that the crew arriving at the island independently is an incredible feat. Back in the city, Robin avoids some suspicious men who are ordered to capture her at all costs. She now wears a long sari-like skirt with a zipped shirt and sunglasses, much like the local women. Robin reads some recruitment flyers from the fake Straw Hats and a poster of Brook's concert, wondering what is going on.
Chopper, meanwhile, was following the fake Zoro, Sanji, and Robin who recognized him from his wanted poster and decided to bring him back to their crew. The suspicious men who were following Robin mistook the fake for the real one and captured her, with Chopper, believing the fake to be the genuine Robin, exclaiming that the men are kidnappers. At the Marine Branch G-1 (formerly the old Marine HQ) Marineford, everyone was in chaos after hearing about the reappearance of the Straw Hat Pirates on Sabaody Archipelago. They intend to summon a force to go and capture them. The scene switches back to Sabaody where the fake Luffy shoots a couple whom he mistook for Usopp and Nami. The locals are too frightened to go against them because of their tendency to shoot anyone who gets in their way. Soon, a skinny man under an animal skin carrying a large bag bumps into the fake Luffy but simply apologizes before leaving. Angered, the fake Luffy shouted at the man,who turns around, revealing himself to be none other than the real Luffy.
- This chapter marks the beginning of the second half of One Piece.
- For the first time since Chapter 144, Oda colored three pages.
- Luffy seems to be finally aware of Hancock's love for him, but bluntly states he has no intention of marrying her. This does not seem to upset Hancock nor changes her feelings towards Luffy, though, and it is played as if this is not the first time Luffy has told her no (and Luffy still seems to be oblivious to her feelings regardless).
- Marguerite has become a member of the Kuja Pirates.
- Luffy has apparently learned everything Rayleigh could teach him in only a year and a half, but this does not say if Luffy mastered it or not.
- Tone Dials are revealed to be used to sell popular music, similar to CDs or cassette tapes.
- Marine HQ has been moved to the New World, with G-1 now in its place.
- It is revealed that a new generation of rookies has gathered once again at Sabaody. However, only two so far have been revealed: "Wet Hair" Caribou (210,000,000) & "Blood-Splatterer" Coribou (190,000,000), two brothers, both pirate captains infamous for killing Marines.
- The Impostor Straw Hat Pirates appear.
- The Straw Hat Pirates arrive at Sabaody after two years.
- Vice Admiral Momonga reappears as the marine in charge of G-1.
- It is revealed that Brook became a world famous soul musician and made the Longarms who captured him into his managers.
- The Straw Hats have been away from each other longer than they have been together as a crew.
- This is the second time someone gives someone else the middle finger in the series. Sanji gives it to the Okama who brought him to Sabaody Archipelago. The first time was when Law gave it to Kid at the Human Auctioning House (both times it happened at Sabaody Archipelago).
- Zoro looks very much like Rayleigh when he was in the Battle in Edd War.
- Sanji's left eye is finally seen, while his right eye is now hidden.
- As shown on the cover page, Franky has now become Battle Franky 37.
- A new Fleet Admiral is mentioned, later revealed to be Akainu.
- This is the second time that while Nami was in a bar when another pirate made a move on her. Sarkies had tried to buy her on Jaya Island.
- Chopper is holding a stick with astonishment effects surrounding it. This is yet another throw back to previous chapters, this time to Skypiea when Luffy was walking with a stick.
- Even after the two year timeskip, the strongest pirates in the New World are still called the Yonko , suggesting someone has filled Whitebeard's seat. It is later revealed that Blackbeard is the new member of the Yonko.
- This is the first chapter of the Return to Sabaody Arc and the Fishman Island Saga.
- first appearance
- Oda has made two mistakes which he corrects in the following chapter. His first is putting Zoro's new scar on his right eye rather than his left. His second is misspelling Monkey by spelling it M-O-N-K-Y in the Impostor Straw Hats' recruitment poster. Both of these are corrected in the anime.
- Previously, an older Luffy was seen in Romance Dawn, Version 1, though the age of that particular version of Luffy is unknown, Oda has apparently chosen to take Luffy's design in a different direction than that one.
- Brook's status as "Soul King" is yet another play on words, as soul can refer to the music genre as well as a person's spirit.
- The color spread reflects the one from Chapter 1, with Luffy and Nami in the same pose as in that spread and with the Red-Haired Pirates replaced by their own crew.