The Girl In The Polka-Dot Dress, By Beryl Bainbridge

The Girl in the Polka-dot Dress could be described, glibly, as a "road novel", since most of the action takes place on the freeways of America as Harold Grasse drives his newly bought, second-hand camper from Maryland to California in the summer of 1968. The portly, bearded Harold's passenger is a young Englishwoman named Rose, who has come to the United States on a one-way ticket with the intention of leaving her dreary lodgings in Kentish Town for ever.

Both Washington Harold, as she calls him, and Rose are on a mission to find a certain Dr Wheeler, who has a rare talent for being elusive. For Rose, whose childhood was overshadowed by domestic violence, physical and verbal, Fred Wheeler, the kindly visiting American in a trilby hat, is nothing less than her saviour. He treated her with dignity and respect at an especially bad time in her blighted life, and her single, overriding ambition is to be reunited with him.

Harold sees the doctor somewhat differently, as a vain, heartless seducer, among other failings, and is possessed of an unspoken desire to exert revenge on him. Their search for the devilish redeemer is the starting-point for Beryl Bainbridge's final book, which was all but finished when she died of cancer in July last year.

It is a pleasure to record that The Girl in the Polka-dot Dress ranks among the finest of Bainbridge's fine works of fiction. The narrative is by turns sombre, terrifying and hilarious. Here is a typically laconic passage: "Mrs Shaefer opened the door to them. She was short and stout and wore a stained apron over a long black dress. Before she said hallo she swore at a man with a ponytail who was standing behind her. She called him a shithead. Rose felt at home. The man with the hair tied back gave Harold a bear hug."

That "Rose felt at home" is a masterly touch, a casual aside that's funnier for being true. A Bainbridge joke is always there to serve a moral purpose, not for the sheer sake of it, as in so much dire comic writing.

Rose is someone that only Beryl Bainbridge could have created. She is reminiscent of the girls in her early, partly autobiographical, novels - resilient against all the odds, sharp-witted when it suits her, annoyingly vague when she's distracted. The great success here is that she and Harold are two of a desperate kind, without their ever acknowledging the fact to one another.

Harold's mother was as satanic as Rose's father, and he is every bit as scarred by memories as she is. The one good thing to emerge from Harold's past is that a halfway decent stepfather left him some money with which to buy stocks and bonds - a financial comfort, at least. Rose has an abandoned baby, an abortion, and failed relationships to remember. Harold worships his departed wife Dottie, who had dozens of specious reasons not to have sex with him, resisting his every attempt to make love to her.

It has to be noted that sexual liaisons in Bainbridge's fiction are often abrupt, occasionally over before they have even begun. Rose has become an expert at lying back and thinking of England or whatever, as a particularly chilling scene brilliantly demonstrates.

Harold and Rose talk a lot, frequently at cross-purposes. We, as readers, share the pain they are unable to express. When revelations come, they are comically expressed: "The night before he'd commented on the way she drummed her fingers on her knees when listening to the radio and she'd said she'd been good at playing the piano, until her mother had battered her knuckles with a spoon whenever she struck a wrong note. That, he'd said, sure was a dumb way to encourage a love of music, and she'd retorted that piano lessons cost a lot of money, and anyway she preferred the ukulele."

Does Rose really prefer the ukulele, or is she jokingly covering up the disappointment she still feels at being denied those piano lessons? Again, a Bainbridge joke makes you laugh and then makes you think - a trait she first employed when she started writing 50 years ago. The Girl in the Polka-dot Dress is full of echoes - from The Dressmaker, from An Awfully Big Adventure, from Injury Time and Harriet Said, the creepiest and most upsetting novel she wrote. It's as if Bainbridge is investing the gauche but knowing Rose with a lifetime's experience of the essential mystery of human behaviour - the mystery that keeps great writers writing to the very end, even as they realise that it will remain unsolved, except by flashes of illumination.

This is not one of Bainbridge's historical reconstructions, despite the fact that the plot hinges on the assassination of Robert Kennedy. A girl in a polka-dot dress was seen running from the Ambassador Hotel in Los Angeles after the six shots were fired. In the final chapters, a diminutive man in a yellow sweater with the ambition of becoming a jockey is introduced, and a crazy hypnotist tells Rose that his name is Sirhan. (Sirhan Sirhan was sentenced to life imprisonment for Kennedy's murder.)

The Girl in the Polka-dot Dress reads like a summation of Beryl Bainbridge's art. It is carefully constructed, as always, but there is a sense in which the author is returning to her roots, using the rich material of her early life in wartime Liverpool to devastating effect, and that Rose is the last repository for those feelings that first inspired her to abandon acting and become a novelist. The constant theme in Bainbridge's novels, the all-important concern, is death. The idea of extinction informs her fiction from the beginning to the end of her writing life. It's no wonder that she loved Dr Johnson, with his great fear of the beyond, and was moved by the plight of the passengers on the Titanic, and those idealistic birthday boys who perished in the Antarctic.

Although she has an absurdist's eye for the random vagaries of life, she never treats death as a laughing matter. She was fascinated by murders, particularly those that take place in living rooms and kitchens and bedrooms. Many years ago, I asked her about her lapsed Catholic faith and she replied that she was happier with hellfire and damnation than the tenets of the second Vatican council. She was the kindest and least judgmental person I have ever known, but I think she believed in the notion of sin and its terrible and terrifying consequences.

Paul Bailey's new novel is 'Chapman's Odyssey' (Bloomsbury)