Volume 55

Volume 55 is titled "Okama in Hell".

Cover
The outside colored cover is pink, and the title logo is gray fading from white, dark gray, and purple. The author's name is written in purple.

Luffy stands in the center in a fighting pose. Behind him are Buggy, Galdino, and Bentham, who strike various other fighting poses. Behind them, from left to right, are Minokoala, Minozebra, and Minorhinoceros. The bottom half of the background is torn away, revealing part of Ace's face.

Chapters

 * 533. Level 4 Inferno Hell (LV4焦熱地獄): Luffy and his allies fall into Level 4 of Impel Down, and Magellan confronts Luffy.
 * 534. Chief Warden Magellan vs. Pirate Luffy (監獄署長マゼランVS海賊ルフィ): Magellan's poisonous ability overwhelms Luffy, but the pirate presses on in order to save Ace.
 * 535. Friends (ダチ): Magellan defeats Luffy and throws him into Level 5, but Bentham prepares to rescue him.
 * 536. Level 5 Frozen Hell (LV5極寒地獄): Bentham breaks into Level 5, finds Luffy, and looks for Ivankov, the only person who could treat Luffy. However, he is attacked by wolves and the brutal cold and passes out.
 * 537. Okama in Hell (地獄に仏): Bentham and Luffy are treated by Emporio Ivankov in a secret location as the prison staff recovers from the chaos.
 * 538. Level 5.5 Newkama Land (LV5.5番地ニューカマーランド): Ivankov uses his Devil Fruit to give Luffy a chance of survival and talks about Level 5.5 and Level 6. Suddenly, Luffy emerges after not even one day, despite the treatment being supposed to take much longer.
 * 539. Emporio Tension Hormones (エンポリオ・テンションホルモン): Luffy regains his strength and proceeds to Level 6 with Ivankov and Inazuma. Meanwhile, Ace is brought out to be taken to Marineford.
 * 540. Level 6 Eternal Hell (LV6 無限地獄): Luffy, Ivankov, and Inazuma reach Level 6 but find that Ace is not there. They break Jinbe and Crocodile out of their cells to help all of them escape.
 * 541. The Likes of Which It Has Never Seen (未だかつてナッシブル): Luffy's group and Buggy's group breaks out of Impel Down, freeing more prisoners in the process. Shiliew, the former warden, offers to help stop the breakout if he is freed.

SBS Notes

 * Oda introduces Pandawoman.
 * Oda explains the background of One Piece Film: Strong World.
 * Kappei Yamaguchi, Usopp's voice actor, gives a Voice Actor SBS.