By the time we have completed the rounds of Madeleine's bookshelves, we know not only that she is writing her English honours thesis on the theme of the marriage plot, but that we're in for a complete overhaul of the classic love story and the Victorian novel.

And what an overhaul it is.

Eugenides manages to reanimate both the coming-of-age novel and the traditional love story in a narrative that is as charged with eroticism, wit, humour and pathos as it is with literary resonances. Eugenides, author of The Virgin Suicides and the Pulitzer Prize-winning Middlesex, is of course famous for doing just that. But The Marriage Plot confounds all expectations. A big, capacious, all-encompassing novel anchored in modern reality and an abundance of detail, it revolves around literature and an unconventional love triangle.

At its apex is Madeleine, an English major at Brown University who we first encounter, together with her idiosyncratic book collection, on graduation day 1982. As the extremely hungover young woman opens the door to her genteel Wasp parents we gradually learn of her love affair with fellow student Leonard Bankhead, a brilliant and articulate biology major who hails from a different social milieu.

But Leonard, the most magnetic member of the triangle, is absent from the family breakfast that Madeleine's mother has planned. And Madeleine, burdened with hangover and heartbreak, doesn't tell her parents she has broken up with him. Undeterred, her mother invites another soon-to-be Brown graduate, Mitchell Grammaticus, (the third member of the triangle) to join them instead. A religious studies major, Mitchell once stayed at the Hanna home at Madeleine's invitation on Thanksgiving, and has always loved her from afar.

Unknown to Madeleine, Mitchell has sworn to marry her one day. Also unknown to Madeleine is that Leonard is in the psychiatric ward of an off-campus hospital. Less than an hour before the graduation march begins, Madeleine learns not just of Leonard's hospitalisation but that he had been diagnosed with manic depression back in his freshman year. Abandoning her graduation, her parents and Mitchell, with whom she argues soon after breakfast, she rushes to the hospital to be with Leonard.

Soon after, the couple reconcile and move in together. At summer's end, they relocate to Massachusetts where Leonard has been awarded a prestigious research fellowship at a biology laboratory. Prescribed massive doses of lithium that depletes his energy and libido, Leonard tries to conceal his illness from his colleagues.

Madeleine, troubled but undaunted by Leonard's wild mood swings - rendered even wilder by his efforts to secretly reduce his medication - marries him.

Meanwhile Mitchell, still convinced that he will marry Madeleine one day, takes a year off, travelling through Europe to India. Here, through voluntary labours at Mother Teresa's Home for the Destitute and Dying in Calcutta, he hopes to reconcile his religious longings with his love for Madeleine.

Eugenides skilfully pitches the twin strands of this pacy triangular romance forward, all the while filling in the past of his youthful characters' lives and laying out his thematic concerns. Madeleine has become an English major 'for the purest and dullest of reasons: because she loved to read'. She was inspired to write her thesis in her junior year after taking an honours seminar titled 'The Marriage Plot; selected novels of Austen, Eliot and James'. As far as her professor was concerned, 'the novel had reached its apogee with the marriage plot and had never recovered from its disappearance. Where could you find the marriage plot nowadays? You couldn't. You had to read historical fiction.' And so Madeleine's plan is to begin with Jane Austen and use a line from Trollope's Barchester Towers as an epigraph: 'the way of true love never works out except at the end of an English novel.'

But this is the 80s, and as Madeleine's thesis stalls, she discovers that the hip students are spouting names like Derrida, Eco, Barthes, Foucault and Baudrillard. 'Almost overnight it became laughable to read writers like Cheever or Updike ...' And so she enrols in Semiotics 211.

However, even as Madeleine deconstructs love according to Barthes, she can't stop herself falling irretrievably in love with Leonard. Books, deconstruction and romantic illusion are central to this tale, which proudly bears an inscription from La Rochefoucauld written in the 15th century, 'No one would fall in love if he hadn't read about it first'.

From Dickens through to Derrida and the deconstructionists, from Beowulf to Balzac and onto Barthes, it is carpeted with literary references. Even the theological titles beloved by Mitchell are integral to the intricate weave of this narrative.

Yet for all its clever playing with literary tropes, it remains very much a character-driven novel. Eugenides has stated that in writing The Marriage Plot he delved deeper into the psychology of his characters than ever before. The result is an ambitious redrawing of the conventional boundaries of literary characterisation.

Eugenides goes to enormous lengths to weave the mundane daily details of his characters' modern lives into the narrative along with their intellectual, literary, financial, sexual and romantic concerns.

From Madeleine's defecating habits to the nature of Leonard's erections to the mechanics of breastfeeding and the 'aristocratic rituals' of tennis, from the chemical complexities of manic depression to the subtleties of Christian mysticism and the science of yeast reproduction, no detail is left unexamined as Eugenides follows the trajectory of the couple's love affair and eventual marriage on the one hand, and of Mitchell's unrequited yearnings on the other.

Eugenides brings, together with an almost discomforting clinical precision, a dazzling emotional acuity to his portrayal of the savage mood swings of Leonard's illness and the muting, often devastating, effects of lithium treatment.

Similarly, Eugenides also blurs the boundaries between mental illness, youthful intensity, romantic illusion and religious experience as he brings the twin strands of this narrative to a satisfying but unexpected conclusion.

It's as if, in recalibrating the marriage plot, he has transmuted the very form of the 19th-century novel into something new, yet comfortably familiar. But the real triumph of The Marriage Plot is its luminous, witty intelligence and the way Eugenides' meticulous prose skates so effortlessly, so magically, between tragedy and comedy with nary a discordant note.