is a Japanese manga series written and illustrated by Hideo Yamamoto. A first series, titled Ichi, was serialized in Shogakukan's manga magazine Weekly Young Sunday in 1993; Ichi the Killer was serialized in the same magazine from 1998 to 2001, with its chapters collected in ten volumes. The series revolves around Ichi, a psychologically troubled killing machine, and his confrontation with the yakuza of Kabukichà Â, Shinjuku.
In 2001, the manga was adapted into a live-action film directed by Takashi Miike. A second live-action film, 1-Ichi, directed by Masahito Tanno, was released in Japan in 2003. A prequel original video animation (OVA), titled Ichi the Killer: Episode 0, animated by AIC, was released in Japan in 2002. The OVA was licensed in North America by Central Park Media and in Australia and New Zealand by Siren Visual.
Using Ichi as a tool, the "Old Geezer" plots to kill the Anjo yakuza family leader, Yoshio Anjo, and steal his money. With Anjo's death, his top yakuza, Masao Kakihara, sets out to find his leader's murderer; Kakihara searches for Ichi, while the younger man effortlessly kills off the remaining Anjo family members. This cycle of killing and searching leads the two closer together, revealing Ichi's psychological manipulation and Kakihara's obsession of pain and torture. When the two finally meet, they confront their deepest and most suppressed desires, resulting in Ichi's recovery and Kakihara's demise.
Written and illustrated Hideo Yamamoto, Ichi the Killer was preceded by a short series, titled , which was published in Shogakukan's manga magazine Weekly Young Sunday in 1993, and its chapters were collected in a single volume, released on August 5, 1993. Ichi the Killer was serialized in the same magazine from 1998 to 2001. Shogakukan collected its chapters in 10 volumes, released from June 5, 1998, to July 5, 2001. Shogakukan republished the series in five volumes, released from April 14 to August 11, 2007. A five-volume edition was released by Shogakukan between February 27 and June 30, 2015.
In August 2024, Seven Seas Entertainment announced that it had licensed the series, releasing it in a five-volume omnibus edition starting on July 29, 2025, which will be followed by the release of a "Volume 0".
A live action film adaptation, directed by Takashi Miike, premiered in Japan on December 22, 2001. A direct-to-video live action prequel film, titled 1-Ichi, directed by Masato Tanno, was released on January 24, 2003.
A prequel original video animation (OVA) by AIC, titled , was released on VHS and DVD on September 27, 2002.
In North America, the OVA was licensed by Central Park Media and released on DVD on September 21, 2004. It was licensed in Australia and New Zealand by Siren Visual and released on February 21, 2005.
Tomo Machiyama of Pulp listed the series among the "Most Hellish (Untranslated) Manga....ever!!!" due to its extreme violence and disturbing content. He observed that while the manga had been banned in some prefectures, it offered a profound existentialist commentary on the nature of existence within a peaceful consumerist society. Machiyama noted its creator, known for Voyeurs, Inc., crafted a narrative that questioned how individuals affirm their own vitality.
Chris Beveridge of AnimeOnDVD described the OVA as an exploration of psychological responses to violence, pressure, and sexuality. While the excessive brutality avoided the dark comedy of Natural Born Killers, it remained unsettling in its execution. Beveridge emphasized its unapologetically graphic nature. Bamboo Dong of Anime News Network criticized the OVA as an exercise in gratuitous sex and violence, arguing that its psychological potential was overshadowed by a preoccupation with visceral thrills. Theron Martin, also writing for Anime News Network, found the narrative plausible in its depiction of a killer's origins, though he criticized the subpar animation. He praised the soundtrack's aggressive techno score for enhancing the OVA's tense atmosphere.
Mike Toole of Anime Jump likened the OVA's crude, unsettling art style to the doodles of a disturbed adolescent, yet deemed it an intentional reflection of the story's brutality. He compared its unsubtle approach to the works of David Cronenberg or Brian De Palma, recommending it primarily for fans of director Takashi Miike or the original Ichi the Killer. Chris Feldman of Animation World Network praised the OVA's self-contained storytelling, noting it required little prior knowledge of the franchise. He remarked that its extreme content would never air uncensored on American television, even on Adult Swim, but considered it essential viewing for existing fans.