"hell is a city much like London," said Shelley.
Certainly, in these two books, it's a scary den where murder stalks the wealthiest enclaves found in the A-Z as well as the poorest.
Ruth Rendell's Saint Zita Society is formed by disgruntled servants working in salubrious Belgravia. Not all are unhappy with their lot, for there are Dickensian below-stairs exploiters as well as thoughtless bankers and aristocrats in the grand apartments above, although the chauffeur who finds himself obliged to service both the mistress and the daughter of the house is uncertain as to his good fortune.
Rendell is excellent on the delicate snobbery of the uneasy territory in between the social classes and the resentful pride of those who might in the past have been termed "companions" rather than ladies' maids, or of "trustafarians" whose families have fallen on hard times.
The novel's plot forms a complex web in which power sways back and forth between employer and employed, where every coming or going has an observer, and it's not long before we anticipate at least two deaths.
Soon a banker is trapped into complicity with his housekeeper, their domestic relationship expanding into Macbeth-style murderous plotting followed by a black farce, with a body carted round the outer purlieus in an attempt to find a safe hiding-place.
The household upheaval which follows profoundly affects the life of Rabia, a nanny who loves her charges more than their real mother but who stands in danger of dismissal.
And, at the very bottom of the social scale, disregarded by almost everybody, is a gardener hearing sinister voices speaking through his mobile phone. We know this must eventually materialise into some horrific outburst, and Rendell keeps us hanging on.
In another part of the same city, Barbara Nadel brings us a new and original pair of detectives in poverty-stricken Stratford East, whose inhabitants are cynical about any possible improvements the Olympic Park can make to their wretched lives.
Here another set of Londoners is impelled towards disaster. Maria, a faded stand-up comedian whose fame reached its apogee 20 years ago, seeks the help of dodgy private investigator Lee Arnold when she begins to experience frightening delusions. Maybe they're not all in her mind, which is frankly rather filthy.
Readers of a gentle literary disposition should be warned that Maria made her name in comedy through the novelty of a woman using obscene language; we are given realistic samples. At the opposite end of the scale is Lee's new assistant, Mumtaz Hakim. Like Rendell's nanny, she comes from a Muslim background and is trying to avoid the "suitable" marriage her family wants for her.
Mumtaz finds herself involved in Maria's nightmarish experiences and forced to play an active part in Arnold's agency, one which exploits her psychology training.
Meantime, riots have spread to other cities and within this background of violent disorder mind-bending religious groups are exploiting converts to their sinister versions of Christianity. This despairing look at the underbelly of London, has a ring of truth.
"While the recession was on, people were going to carry on boozing, drugging and shagging their way out of their misery".