Koroshiya 1 THE ANIMATION: EPISODE 0 is a oVA anime that premiered in fall 2002.

About the production: the story comes from a manga, there is 1 episode of about 45 minutes and its current status is "finished".

Its main genres are action, drama, horror and psychological, with themes such as Yakuza, Male Protagonist, Martial Arts and Gore.

On AniList, Koroshiya 1 THE ANIMATION: EPISODE 0 has an average score of 54%, an average score, and appears on 3,163 users' lists.

A masochistic mobster meets his match in the dark streets of Tokyo. His nemesis, Ichi, is a psychopathic killer with an unrelenting thirst for bloodshed. A horrifying secret burns in his mind, and his hands deal death without mercy. At last, the shrouds of mystery are parted to reveal the origin of the monster. The city will know its greatest fear at the unveiling of Ichi the Killer. (Source: Anime News Network)

Official synopsis from AniList.