Dr. Hogback is a globally renowned physician, praised by Chopper for saving as many lives as there are stars in the sky. However, he vanished from public view one day, causing significant upheaval in the medical community. Nami, Usopp, and Chopper encounter him on Thriller Bark, where he claims to be researching life and death using the island's zombies.
This explanation turns out to be a deception when the crew uncovers that Hogback himself created the zombies and is part of Gecko Moria's crew. Moria infuses the zombies with stolen shadows, transferring the abilities and personalities of their former owners into the undead bodies. Hogback later meets with Gecko Moria, Perona, and Absalom to discuss the creation of Zombie #900 and the removal of Luffy’s shadow.
Hogback faces off against Chopper, who, as a doctor, despises Hogback’s experiments for being driven by personal gain rather than advancing medical science. To his dismay, Chopper finds that Hogback has prepared Jigoro and Sanji's zombie for battle. After Chopper and Robin's defeat, Hogback reveals his true motives: he never cared about saving lives and went into hiding because too many people sought his help, which he only pursued for financial gain.
Robin outsmarts Hogback by instructing Jigoro and Penguin to jump out the window. Despite this, Hogback faces betrayal from his prized zombie version of Cindry. Before Chopper and Robin can finish him off with a wrestling move, Oz's rampage interrupts them. As Hogback attempts to speak with the giant zombie, Oz crushes him underfoot. However, it is revealed in chapter 483 that Hogback somehow survived the attack.
Like many One Piece characters, Hogback has a unique laugh (fosfosfosfos). Many members of Thriller Bark seem inspired by classic horror movie archetypes; Hogback appears to be modeled after mad scientists, particularly Dr. Frankenstein.
