Tokyo Year Zero, by David Peace

David Peace made his name with a series of novels set in Yorkshire against the background of the Yorkshire Ripper murders. Then he turned his attention to football in The Damned Utd, a fictionalised, widely praised account of Brian Clough's brief engagement as manager of Leeds. His new book, Tokyo Year Zero, is on the face of it a departure from his Yorkshire novels, set in Japan (where Peace now lives) and promised as the first novel in a trilogy.

It opens in August 1945, with the discovery of a woman's body in a flooded air raid shelter, forcing Detective Minami to wade through water contaminated with raw sewage to retrieve the corpse. This scene, immediately preceding the Emperor's announcement of surrender, is a grim introduction to a city devastated by war; it also functions as a metaphor, an image of the squalor and degradation facing Minami and his men as they struggle to restore some semblance of law.

The crime is solved on the spot when the military police arrive, seize the chief suspect, an elderly Korean man, and beat him to death. Case closed – until exactly a year later, when the bodies of two more young women are found in Shiba Park. One is a fresh corpse, raped and murdered according to the forensic evidence, but the other is little more than a skeleton with a distinctive set of clothes. Minami heads the team of detectives investigating the second murder, and Peace's extensive research into the period pays off as his characters try to do their job amid police corruption and gangland wars.

Identification of the first body quickly leads to her killer, a man called Kodaira Yoshio. Kodaira was a real person, convicted of the rape and murder of 10 women, including the two found in Shiba Park, and executed in 1949; the second victim in the park was never identified, even though Kodaira confessed to the killing, and it is this historical fact that gives Peace his opening. The novel's premise is that the unidentified woman does not belong in the series, a fact that only Minami, for reasons he cannot reveal to his colleagues, appreciates.

At one level, this is an unrelenting portrait of Tokyo at the end of the Second World War, physically and mentally shattered by defeat. The Americans are in charge, mocking Japanese customs and treating men, women and children with casual brutality. The hard-pressed detectives put up banners announcing their investigation, making a successful outcome a matter of honour.

Peace's evocation of life under occupation is not for the squeamish as children and dogs starve in the rubble of bombed buildings and women trade sex for a handful of rice. Just about everyone is coarsened and brutalised, not least Minami, whose hallucinatory recollections of his wartime experiences suggest he is guilty of war crimes; even his identity is in question as Kodaira appears to recognise him, claiming to have once known him, with another name, when they were both soldiers.

Peace's portrait of a man breaking down is central to the novel and also the source of its problems; unreliable narrators are not uncommon but one who is quite possibly insane presents special difficulties. One of Peace's methods of conveying Minami's mental turmoil is a double narrative in which his inner thoughts appear in the text in italics. The same phrases repeat throughout the book, symbolising a persistent itch - Gari-gari in Japanese – which irritates the reader almost as much as the detective, though for different reasons:

"I itch and I scratch. Gari-gari. My arms and my legs. I turn their shoes to face the door. I itch and I scratch. Gari-gari."

This is transparent artifice, as is the sprinkling of Japanese throughout the text, necessitating frequent consultations of the glossary at the back even though the characters are all supposedly speaking the same language. These devices make the novel an arduous read, and also raise questions about what would be left if its unremitting feverishness and brutality were taken away. There is a laddishness about this story of defeat and disintegration which may appeal to some readers, but it left me longing for more subtle methods of narration.

Faber £16.99 (355pp) £15.29(free p&p) from 0870 079 8897