Chapter 644

Chapter 644 is called "To Zero".

Cover Page
From the Decks of the World Vol. 27 - "Jaya - South Bird ♥ North Bird → West Bird & East Bird".

Short Summary
Noah continues falling toward Fishman Island while a flashback of Hody's appears. In the Fishman District, Hody and the New Fishman Pirates officers were taught as kids that the humans are an inferior species and they should be punished by heaven. The flashback moves forward in time when Hody was a Neptune Army member and he and his crew commit crimes, celebrate the death of Otohime, and start producing Energy Steroids and the flashback ends. Fukaboshi gives an emotional speech to the whole island about the cause of this event and begs Luffy to create a new beginning. Luffy then tells Fukaboshi to leave everything to him and his crew. After the discussion ends, Hody catches up to Luffy and Shirahoshi and Luffy punches him with an exploding punch.

Chapter Notes

 * There are north birds, east birds, and west birds in addition to south birds. Apparently the south bird fell in love with a north bird and their kids are the east bird and west bird.
 * More of the past of the New Fishman Pirates is revealed
 * The air bubble is succesfully placed around Noah.
 * For the first time, Luffy uses a Gear Second attack without using "Jet" in its name. Because it is an attack that would be impossible to do in his normal form, it is not a jet version of an attack.
 * In one of the panels, the New Fishman Pirates are shown wearing black hoods and burning another fishman's house for helping a human. This is similar to how the Ku Klux Klan wore white hoods and burned downed other southerners' houses during and after the Civil War for helping people of African decent that were being discriminated against.
 * It is revealed that Zeo is a chemist, as he was the one that Hody had replicate the drug.