Hidan is a character from the second part of the Naruto series, known as a missing-nin who defected from the hidden village of Yugakure, the Village of Hidden Steam. His origin is rooted in deep disillusionment; after his village transitioned from a military shinobi stronghold into a pacifist tourist destination, Hidan became enraged. Believing that shinobi were destined only for killing and violence, he massacred his neighbors and left, eventually joining a cult-like faith known as Jashinism. This religion, which worships a deity of the same name, preaches a doctrine of absolute slaughter, where anything less than utter destruction is considered a sin. Hidan became the first successful test subject of the cult's forbidden jutsu experiments, which granted him his most defining trait: immortality. Eventually, he was recruited into the criminal organization Akatsuki, where he was partnered with Kakuzu, a fellow immortal rogue ninja.

Hidan possesses a volatile, foul-mouthed, and deeply disrespectful personality. He frequently uses profanity and complains about nearly everything, showing little regard for allies or enemies. He is the only known Akatsuki member who openly defies and expresses a willingness to kill the organization's leader, Pain, showing no deference to authority. The only entity he appears to respect is his god, Jashin, though even that reverence is often expressed through violent rituals. He openly holds his partner, Kakuzu, in contempt for his constant blasphemy, his obsession with money, and his ridicule of Hidan's religious practices. Despite this constant bickering, the two form an effective combat unit known infamously as the Zombie Combo. Hidan has absolutely no moral restraints when it comes to killing; he views murder not as a crime, but as a religious calling and a form of worship. He is a sadist who derives genuine pleasure from making his opponents' deaths as painful and protracted as possible. Given the mechanics of his curse, which requires him to inflict harm on himself to hurt his target, he also displays a notable masochistic side, openly relishing the shared pain. However, his immortality has made him incredibly arrogant and reckless in battle, often disregarding strategy beyond the need to draw an opponent's blood. While not unintelligent, as he has shown the ability to analyze the limits of techniques like Shikamaru Nara's Shadow Imitation, he is far outmatched in tactical genius by the likes of his partner or his enemies.

Hidan's primary motivation is the spread of the Way of Jashin. He considers his supreme purpose to be forcing the world to acknowledge mass killing as a divine principle. He believes that using Akatsuki's power is a viable means to achieve this goal of a world built on slaughter. His role in the story is central to one of the most pivotal arcs of Naruto Shippūden. He and Kakuzu are dispatched to capture the Two-Tails jinchuriki, Yugito Nii, which they accomplish successfully. They then travel to the Land of Fire, where they slaughter the monks of the Fire Temple for a bounty. This action draws the attention of Konohagakure. Hidan engages Team 10, consisting of Shikamaru Nara, Ino Yamanaka, Choji Akimichi, and their sensei, Asuma Sarutobi. In a brutal battle, Hidan successfully uses his curse to kill Asuma, a moment that serves as a major turning point for the younger generation of Konoha ninja and fuels a deep-seated revenge plot.

His key relationship is with his partner, Kakuzu. Their pairing is one of pure pragmatism rather than friendship. Because Kakuzu has a history of murdering his own partners in fits of rage, he is uniquely suited to work with Hidan, as the immortal Hidan cannot be killed. This allows Kakuzu to unleash his destructive power without restraint, even catching Hidan in the crossfire. For Hidan, this partnership provides the battlefield chaos he craves. Despite their mutual disdain, there is a hint of twisted concern when Hidan panics after nearly killing Kakuzu while under an enemy's control. Hidan's ultimate development, or lack thereof, is defined by his hubris. His arrogance leads to his downfall at the hands of Shikamaru Nara, who seeks to avenge Asuma. Using superior strategy, Shikamaru tricks Hidan into consuming not his own blood, but Kakuzu's, forcing Hidan to destroy one of his partner's hearts. Shikamaru then separates Hidan from Kakuzu, leads him into a trap filled with explosive tags, and detonates them, blowing Hidan's body apart. His severed head falls into a deep hole, and Shikamaru collapses the earth on top of him. Though his immortality prevents him from dying, he is left buried alive, slowly perishing from malnutrition in a secret forest controlled by the Nara clan, effectively removing him from the story.

Hidan's notable abilities are uniquely tied to his immortality and his religious curse technique. As a result of the Jashin experiments, he cannot die from virtually any physical trauma, surviving decapitation, impalement, and dismemberment. He retains consciousness and speech even when his head is severed, though he requires his body to be reattached to control his movements. His primary weapon is a large, crimson triple-bladed scythe attached to a long cable, designed specifically to draw enemy blood rather than inflict fatal wounds. His signature technique is the Curse Technique: Death Controlling Possessed Blood. After consuming a target's blood, he draws the symbol of Jashin on the ground using his own blood. Standing within this diagram, his skin turns black with white skeletal patterns. This creates a voodoo-like link where any damage inflicted upon his own body is simultaneously and unavoidably inflicted upon his linked victim. Because he is immortal, he can stab himself through the heart or pierce his own organs to kill his opponent while he himself survives, making him an extraordinarily dangerous and unique adversary.