Sean French and Nicci Gerrard

THE husband and wife writers who go by the name Nicci French begin their latest book, Has Anyone Seen Charlotte Salter?, at a party to celebrate the 50th birthday of a businessman whose wife has suddenly gone missing.

Authors Nicci Gerrard and Sean French are not only hugely successful novelists – they have also campaigned in our sister paper the Islington Tribune about the state of our overcrowded prisons.

The couple, who once lived close to Pentonville, still campaign to improve prisons, and find visiting the institutions useful in research for their writing.

Their new book, however, has a tranquil setting in a Suffolk village. It’s a long way from Tufnell Park where Sean grew up. A former William Ellis School pupil, he is the son of the late great Observer film critic Philip French OBE.

In the latest novel, missing Charlotte, 47, is wife of birthday man Alex, and mother of three adult sons and one daughter aged 15.

Charlotte is described as highly popular with most people, warm hearted and full of life. But daughter Etty, 15, fears the worst – that something terrible has happened to her mum.

The police are called but still there’s no real concern until they find Charlotte’s new coat discarded down by the river.

Etty’s brothers are now all hugely worried and upset. They are Paul, 20, a biology student at Bath University; Ollie, 19, on a university gap year and Niall, 24, who works as a project manager.

Suddenly the drama intensifies with the news that a close friend of Charlotte, Duncan Acklerley, has been found drowned in the river. Police even suggest he might have killed Charlotte.

Soon Charlotte’s husband Alec is also the centre of accusations of mistreating his wife and having affairs and there’s a suggestion she was planning to leave him and take Etty.

But police can find no proper leads. For the next five years the children suffer the stress and anxiety of losing their mum, and then there’s more tragedy. This time the youngest son, Paul, can’t cope with the pain of loss of his mum and commits suicide.

The book is in two sections. In part two it is 30 years later. Alec now suffers from dementia and confuses daughter Etty with his long-lost wife Charlotte. Etty is a solicitor in Clerkenwell but still determined to find out what happened to mum.

Finally, a new woman police detective is asked to re-examine the case where three decades earlier male cops could not decide what had happened.

Detective Inspector Maud O’Connor points the finger at an extremely unlikely culprit. The killer finally admits the truth.

I found the book hard to put down. The characters are believable, the plot plausible and authentic.

Talking about their prison campaign, Nicci, who now lives with Sean in Hackney, said that she was glad to air her views in the Review. “Just the experience of spending a few hours inside a prison is a revelation,” she said. “You leave the outside world with a terrifying abruptness – keys jangle, door after door shuts behind you.”

One of their previous novels, The House of Correction, is set in a prison.

Nicci said: “There is something very haunting about many prisons. The whole system is in desperate need of overhauling. We visit a lot of prisons and like to talk to prisoners. It’s one of the most overcrowded, under funded, overlooked, disregarded issues in our country.”

She has also visited the institution that replaced Holloway women’s prison, now based in Surrey. “I don’t think women should be in prison unless they are a physical danger to people. They can do community service and atonement outside prison.”

Sean added that in many of the Scandinavian prisons they have visited there is a “real feeling of rehabili­tation. The reoffending rate is subsequently a fraction of the UK.”

• Has Anyone Seen Charlotte Salter? By Nicci French. Simon & Schuster, £18.99