Okada Izo

Okada IzoOkada Izō ( February 14, 1838 – June 3, 1865) was a Japanese samurai of the late Edo period, feared as one of the four most notable assassins of the Bakumatsu period. He was born in Tosa to the gōshi Okada Gihei, who had been a peasant but had bought the gōshi rank. Izō and Tanaka Shinbei were active in Kyoto as assassins under the leadership of Takechi Hanpeita.

Izō in fiction
Several films feature Okada Izō as protagonist, most notably Hideo Gosha's Hitokiri (1969) (portrayed by Shintaro Katsu) and Takashi Miike's Izo (2004). Most recently, the NHK Taiga drama Ryōmaden (2009) features him several times as one of Sakamoto Ryōma's friends and Takechi Hanpeita's assassins. He was portrayed by Japanese actor Takeru Sato.
In manga and anime, Nobuhiro Watsuki based the character Kurogasa Udō Jin-e of his manga series Rurouni Kenshin on Izō; the author admits that the character bears little resemblance to Izō. Hideaki Sorachi also based Nizo Okada, a character in his work Gintama, on Izō. It is also possible that a character from One Piece, Izô, commander of the 16th division of the Whitebeard Pirates, is based on Okada Izô. This, however, remains unconfirmed by the series' creator, Eiichiro Oda.
Masami Kurumada, author of the popular Saint Seiya manga series, more recently added a character to his work, called Capricorn Izō, who is inspired by Okada.
Okada supposedly appeared as well in Kengo, a video game based on 9 legendary swordsmen.