Akira Nishiguchi (西口 彰, Nishiguchi Akira, December 14, 1925 - December 11, 1970) was a Japanese serial killer and fraudster.

He murdered five people and engaged in confidence scams. While engaging in confidence scams, he murdered two people, was put on the most wanted list, and killed three others while escaping.

His crimes shocked the Japanese police because they thought that fraud was not necessarily related to serial murder. The police also regretted that they couldn't have found Nishiguch before a 11-year-old girl found him. A prosecutor called him "the Black Gold Medalist in history".

A Roman Catholic, he retracted his final appeal on August 15, 1966 — the assumption of Mary. He was executed on December 11, 1970.

Ryuzo Saki published a book about Nishiguchi, which became the basis for the film Vengeance Is Mine.

Nishiguchi Akira – Japan

A best-selling, prize-winning “documentary novel,” and a film made from it, tell the story of Nishiguchi Akira, who went on a 78-day crime spree across Japan in late 1963, murdering five people. The book and the film, Vengeance Is Mine, accurately portray the exploits of the Japanese serial killer, who befriended, swindled and robbed his victims before murdering them.

Akira went on the run after killing two men and robbing them of $750. During his rampage he spent two five-day periods at a cheap hotel in Hamamatsu where, on November 18th, 1963, he strangled the woman proprietor of the hotel and her mother. Later he befriended an elderly lawyer in Tokyo who he robbed and murdered on December 29th.

He was finally caught in Kyushu after being recognised by an 11-year-old schoolgirl who had seen one of the half-million wanted posters pasted up all over the country. He was hanged on Friday, December 11th, 1970, aged 45.