CREATORS OF EXTENDED crime series have a real problem deciding how long to let their characters survive professionally. Some have said that ten novels is enough for any one sleuth. Others allow the realities of police employment to decide when their detectives must retire.

Ruth Rendell introduced her many fans to Inspector Reg Wexford in 1964 in From Doon with Death. Even if he had been promoted miraculously young, he must be way past the statutory retirement age by now.

He also seems out of tune with today’s world, despite all his awareness of computers and the DNA database. It’s not only his grumpy reactions to things such as Sunday shopping and the way that young couples who are already living together go through the formality of getting engaged that make him an unlikely figure in modern policing, but also his present case. With a corpse discovered by a man walking his dog and a neat but unlikely motive for murder, Not in the Flesh is essentially a traditional English village mystery, although it has none of the cheerful cosiness associated with Mayhem Parva. Almost every character is unhappy or unpleasant and many are both. Old age, disappointment and dirt lie over the pages like a peculiarly nasty fog.

Wexford, now a Chief Inspector, is much given to gloomy thoughts. “The stench of old clothes and mothballs was unpleasant. Mice had been eating the old flock mattress. It was strange, Wexford had sometimes thought, how rodents could eat unpalatable, nutrition-free substances and apparently thrive on them,” is one typical passage. “Strange, he thought, that death and subsequent decay wipe away age and sex and every distinguishing feature so that nothing is left but bare bones and a rag or two . . . How comforting it must have been when men . . . believed that the body is but a sheath for the spirit which, at the point of death, flies away . . .” is another. It’s enough to make you cut your throat.

Rendell does introduce some colour, particularly in her evocative descriptions of the country around Kingsmarkham, and there is a little happiness. The first body is discovered by an elderly villager who has just presided over the death of his brother (happiness is relative in this novel) and inherited his truffle-hunting dog, which makes many successful finds around Kingsmarkham. Indeed, at one moment the dog disinters a truffle big enough to sell for “more than the whole of his winter fuel supplement”. Oh, joy!

The most alluring characters belong in one of the subplots, which deals with female circumcision. There is now a fairly large Somali community in Kingsmarkham and two of its more liberated women members are trying to prevent little girls being cut to satisfy the cultural customs of their parents’ generation. Although Reg’s wife, Dora, does not know exactly what female circumcision entails, one of their daughters is a social worker on the lookout for it and the other is campaigning to raise awareness among the Somali population. Few of them have heard of the British law that means they can be sentenced to 14 years in prison for having their daughters mutilated. The passage when some of Wexford’s team rush to save a girl known to be at risk provides a moment of real tension.

But other parts of the narrative suffer from the laboriousness inherent in the very nature of the village mystery. Detectives have to interview innumerable people, some of whom are irrelevant and quickly disappear, asking questions about the same few events and pieces of evidence. And all the suspects have to be capable of murder, which means, as Michael Innes pointed out years ago, that none can have wholly rounded characters. If they had, the solution would be obvious from the start. Rendell, a brilliant creator of complex and credible characters in her Barbara Vine psychological novels, does her job here with customary efficiency. Almost everyone involved seems potentially murderous.

In a welcome improvement on the classic village mystery model she gives Wexford a realistically sized team but, like the suspects, they are distinguished by bundles of habits and attitudes rather than fully formed personalities. Occasionally a minor character shines vividly for a moment, for example young PS Peach from the uniformed branch, but unfortunately he disappears all too soon.

And it is surprising how many small contradictions and repetitions there are. One moment Wexford is boasting about his accurate hunches, the next he is disapproving of intuition because facts are all that matter. We are told several times that not all Somalis are Muslims. Some are Christian, characters explain, others, animist.

One Somali woman is described as having a slenderness that “could be seen to be natural and not associated with starving herself” only a few pages after an English woman has “the thinness which is natural and unaffected by dieting or overeating”. In her stand-alone novels, Rendell has used language with great suppleness and precision, and a bit more of that would have helped to counteract the general air of tiredness and despair.

Of course murder should depress everyone, and the realities of old age and illness can never be fun, but a little more excitement or even optimism would have lightened the load of human misery represented by Reg Wexford and his companions in Not in the Flesh.

Natasha Cooper appears at the Harrogate Crime Festival this weekend 0845 1308840; www.harrogate-festival.org.uk/ crime

Not in the Flesh by Ruth Rendell

Hutchinson, £17.99; 266pp

Buy the book here at the offer price of £16.19 (free p&p)

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