Time Out says
When the 25-film Zatoichi series came to an end (or, more exactly, in the gap between the film and TV series of Zatoichi), Katsu looked around for other stories which might generate lucrative series – and found this ‘adult manga’ by Kazuo Koike and Takeshi Kanda, the Ichi the Killer of its day, about an Edo policeman with a remarkable phallus which he uses to force confessions from female suspects. Kamisori Hanzo (‘Hanzo the Razor’) hates the rich, despises both privilege and corruption and makes it his business to serve the poor; he has reformed criminals as servants and is locked in an unending battle of wits with his hopelessly compromised boss Onishi. This inaugural film takes its time to establish everything and has a negligible plot about a lady in the imperial court using a convicted thug as muscle to shield her secret liaison with a kabuki actor. The explications of Hanzo’s masochism (he pummels his penis like a swordsmith forging a blade) are certainly startling, if not as shocking as the score, which sounds like out-takes from Shaft. Two sequels followed, both written by Yasuzo Masumura, one also directed by him.