Sometimes it seems as if Ruth Rendell’s heart just isn’t in all that killing any more. Certainly, her latest book, The Saint Zita Society (Hutchinson, £12.99), works best as a portrait of modern London, sharing many of the characteristics of novels like John Lanchester’s Capital and Sebastian Faulks’s A Week in December. The murders, when they finally happen, not only go unsolved, but even largely uninvestigated. They also feel rather sketchily plotted and weirdly peripheral to the action.

The setting is an upmarket street in Pimlico whose inhabitants include a paediatrician, a classic gentlewoman of the old school and, naturally, a horrible City financier and his lazy wife. But also living there is a multi-national assortment of au pairs, drivers, nannies, cleaners and gardeners. Meeting regularly in the local pub, these people provide much of the novel’s impetus, as well as its title — Zita being the patron saint of servants.

Rendell hasn’t perhaps kept up with the latest anti-racist fashions, happy as she is to generalise about such things as ‘the Caribbean ready sense of humour’. Yet, she remains as good as ever at the careful delineation of social hierarchies, both obvious and hidden. Nor has her eye lost any of its famous steeliness. Particularly chilling, is the relationship between the gentlewoman and her companion: two women who’ve lived together for 60 years without ever liking each other much.

The Saint Zita Society, then, may lack the old-style Rendell thrills, but the result is still a deft, entertaining and often quietly angry book.