Chapter 597 is titled "
Zoro had defeated all the Humandrills but returned to Mihawk's castle and begged the Shichibukai to train him. Mihawk at first refused and was bewildered but agreed when he realized the reason was not for Zoro's own benefit. The swordsman revealed the message Luffy sent his crew members: the Straw Hat Pirates will reunite again in 2 years, after getting stronger. Meanwhile, Luffy started training with Rayleigh on Rusukaina Island and learned about the three forms of Haki.
Zoro began begging to Mihawk to teach him the ways of the sword. Mihawk, who was rather disgusted by Zoro's begging, wished to get rid of him thinking he had overestimated his abilities. Zoro informed Mihawk that he defeated all the Humandrills and that he only needs to defeat him. Mihawk, who was rather surprised by all this, found the request to teach the swordsman that wants to surpass him someday absurd. However, Mihawk understood that Zoro wanted to get stronger for Luffy, and not for his own ambitions. Mihawk then decided to begin training him once his body was healed. Then Zoro, who was now bandaged up again, told Perona what Luffy's tattoo meant. The tattoo reads
3D2Y. Zoro explains the original plan was for the Straw Hats to meet up in three days but now it is in two years (hence why the 3D, standing for three days, is crossed out), so all the Straw Hat Pirates in their various locations all got the message and understand they will meet up in two years at the Sabaody Archipelago.
The story then went back to a few days earlier in the Calm belt on an island called Rusukaina Island. Luffy and Rayleigh, along with the Amazon Lily tribe and Jinbe had arrived on the island. Jinbe departed and he and Luffy thanked each other for all the other's help and Jinbe told Luffy he will be waiting for him at Fish-Man Island. Hancock wished to give Luffy food as he began two year training session with Rayleigh on the island but Rayleigh, turning down the offer, informs Hancock that the reason they came here was solely for Luffy to learn survival skills on the 48 season island that changes every week. This made Hancock get angry at Rayleigh, but she calmed down when Rayleigh told her it was for Luffy's own good. Hancock then left the island with the Amazon Lily tribe. Rayleigh then explained that the island is uninhabited but there once was a civilization that died off due to the adversity of the island's natural environment and that the island currently has about five hundred or so animals living on it that Luffy would have a tough time defeating.
Rayleigh explained the ability of Haki and why Luffy must learn to strengthen it. He explained all 3 types of Haki while he took down a giant elephant without physically touching it as a demonstration for each type. He then explained Kenbunshoku Haki, (which is known as Mantra on Skypiea) or the ability to sense the opponent's presence and accurately predict their next move. He explained Busoshoku Haki, which is the power to "armor" one's body with haki, enabling one to attack without touching someone as well as nullify Devil Fruit abilities, particularly allowing one to physically touch a Logia-type Devil Fruit user. And finally, he explained the third type called Haoshoku Haki, which is the power of intimidation.
This power is rare and only a select few people can learn it. Rayleigh explained that Luffy must learn to control this power since he could intimidate innocent people if he cannot control it. So Rayleigh decided that in two years, with Luffy's potential, he is going to make him learn the basics of all three forms of Haki and as Luffy gets stronger, he will decide which one he should strengthen on his own. Luffy then leaves his straw hat and vivre card behind on a rock and claims that the pirate "Straw Hat Luffy" is going on vacation.
- Zoro figures out that Luffy's message on his right arm means the Straw Hats will not meet after three days but two years. That is why the title is
3D2Y with 3D crossed out.
- Mihawk agrees to train Zoro.
- Haki is further explained and it is revealed to have three types: Kenbunshoku, Busoshoku, and Haoshoku.
- Mantra, used by Enel and his priests in Skypiea, is finally confirmed to be a form of Haki, in this case another name for Kenbunshoku Haki.
- Sentomaru is confirmed to be a Busoshoku Haki user.
- It is revealed that it was Haoshoku Haki that Shanks used to scare off the Lord of the Coast 10 years ago.
- Also coinciding with the two year timeskip, is the beginning of the longest manga break between chapters of One Piece (excluding Shonen Jump Magazine's normal breaks); 4 weeks. However, Eiichiro Oda himself only rested for one week before continuing work.
- The cover page is one of the few non-side-story chapters with no animals along with the characters.
- This is the last chapter of the Post-War Arc and the Summit War Saga. In addition, this chapter marks the end of the first half of One Piece.