The Other Side of You By Salley Vickers

On the couch with Caravaggio

Salley Vickers's new novel has two hearts. The first is an extraordinary, boundary-busting seven-hour exchange between a psychiatrist and his patient, a middle-aged woman who has attempted suicide for reasons that she has been unwilling to disclose and who seems intent on trying again. The second is an account of a briefly brilliant but doomed love affair between a married woman and an art historian, Thomas Carrington. The failed suicide and the married woman are one and the same, Elizabeth Cruikshank.

Part of the long conversation in the psychiatrist's chair is her reliving her relationship with Thomas. But it is more than one-way traffic. When Dr David McBride manages to find the key that starts Elizabeth talking, he discovers that what she has to tell unlocks in him buried and distorted memories of his role in the death of his six-year old brother.

Crucial to this chain of events and the eventual redemption of both main characters is art - which will not surprise anyone who has read Vickers's highly-acclaimed novels, Mr Golightly's Holiday and Miss Garnet's Angel. It is one of her distinctive themes. So only when he mentions a Caravaggio painting in the National Gallery does McBride's absorbing struggle to bring Elizabeth back to something approaching life bear such remarkable fruit.

In their own discussion over a Carvaggio painting, Thomas and Elizabeth explore one of the most striking proposals of this novel. He highlights what he sees as the essential truthfulness that an artist can reveal, which everywhere else is disguised under "tinsel and flummery, precepts and morals and habits and fibs and shams". He then explains to Elizabeth that "a real artist knows the other side of himself better than the side he's in at the time. You don't paint as you are; you paint as you?re not. But you only know what you're not through knowing what you are."

Vickers's novel - its title taken from TS Eliot's The Waste Land - gives this observation dramatic form. Knowing that "other side of you", whether you be artist, doctor, onlooker or, in the case of Elizabeth, someone who believes she has no reason to go on living, is what ultimately drives the characters. And crucial to reaching the other side is, Vickers suggests, absolute truth and painful honesty.

So Thomas will not disguise his feelings for Elizabeth, but she instinctively retreats and so betrays his complete trust - which leads in turn to her losing him forever. Wiser as a result of that loss, Elizabeth then approaches her psychiatrist with such unflinching directness that he himself is pushed to journey to his own other side and admit his guilt about his past and his dissatisfaction with his present. The two hearts of the novel end up beating as one.

There is something rare and very special about Vickers as a novelist. In exploring the connections between faith and imagination, art and redemption, religion and science in an intelligent, unusual but very readable way, she manages to touch something buried deep in all of us. It gives her work a quietly compelling quality.

Peter Stanford's 'Heaven: a traveller's guide' is published by HarperCollins