Sex And Stravinsky, By Barbara Trapido

From her debut novel, Brother Of The More Famous Jack, Barbara Trapido has displayed a relish for comic plots that are Shakespearean in their blithe disregard for realism. They are perfectly realistic in their settings, at least, and in their portrayal of tangles of mismatched affections and erotic misreadings, but they gleefully pile coincidence upon coincidence, symmetry upon symmetry.

Because the characters are so recognisable, their emotions so "real", the coincidences and the knowing employment of tropes as old as Menander – separated twins, secret paternity, one sibling unjustly favoured – never feel mechanical. Rather they emerge as elegant contrivances, as much a pleasure as the story they advance. The effect is interestingly two-edged; one moment Trapido is flattering her reader's intelligence, as though saying, "We're both too well educated ever to forget that this is only a novel," the next piercing their heart with an unexpected shaft of candour.

Sex and Stravinsky straddles Trapido's two worlds – South Africa, where she was born, and Oxford, where she has spent much of her life. Its plot is set against the social upheavals in both settings between the late 1970s and the present. Caroline is a leggy, Australian amazon of daunting ingenuity and resourcefulness, the sort of woman who can dress herself and her daughter in great style by running up clothes from vintage curtain fabric. She lives in a cunningly converted double-decker bus with clever South African Jewish Josh, who is a dance academic, a Harpo to her Hippolyta.

She's a headmistress, seemingly invincible, but has two Achilles heels – a grotesquely selfish mother, parked on her by her equally unlovable fundamentalist Christian sister, and a moodily unreachable daughter with a secret ballet fixation. Meanwhile, in an elegant South African suburb, Josh's childhood sweetheart, Hattie, is imprisoned in prosperous marriage to sexy, brutally capable architect Hermann, mother to three beef-fed Aryans who are aghast at her feyly European ways. She makes a quiet living writing the ballet novels Josh's daughter guiltily devours and is hopelessly out of touch with her bulimic, permanently furious youngest daughter.

It's a foregone conclusion, when Josh is booked to attend a dance conference on Hattie's doorstep, that the two families will collide and rearrange themselves. The pleasure lies in the ways Trapido will allow her characters to stumble towards their happy(ish) ending and in the shafts of self-discovery she grants them along the way.

In Frankie and Stankie, Trapido revisited her South African heritage and wittily showed her heroine's snail-pace dawning of political consciousness. That novel's many admirers will appreciate this one's abrasive subplot. Josh's liberal activist parents, a brilliant, unworldly couple who think nothing of risking their lives for the anti-apartheid cause, effectively adopt their black maid's illegitimate, pale-skinned, sensitive son, Jack, rescuing him from township squalor. Far from growing up to be as public spirited as they were, he becomes a style-obsessed narcissist, selfish and wary. It's a fascinating character study in a novel where even the monsters are admirable.

The novel is shot through with references to the commedia dell'arte and Pulcinella, but Jack springs from a darker, less comforting comic vision – a Feste or a Jacques. Even as the tendrils of Trapido's plot reach out to offer him a rightful claim to a place in her bigger, happier family of realigned partners and doubly mothered daughters, he remains unreachable and discomforting.

Patrick Gale's latest novel is 'The Whole Day Through' (Fourth Estate)