Adashir Vakil's second novel is deceptive. His impressive debut, Beach Boy, was shortlisted for the Whitbread First Novel Award, and at first glance One Day looks like a featureless follow-up, just another tired treatise about the navel-gazing of a middle-aged couple whose dreams and aspirations have floundered on the rocks of reality.

The cleverness of this book, however, is the way in which it takes a familiar theme and manipulates it to make a whole series of thoughtful statements about the state of modern relationships and the struggle to reconcile emotional necessity with primal animal desire in a new millennium.

The story is woven around 24 hours in the life of a couple living in London in 1999. Vakil has tried to be too clever by making the date March 15, allowing for several 'Ides of March' references. While the concept of examining the events of one day may have been stolen from a popular US television drama series (24), the way in which an apparently ordinary day encapsulates and defines the lives of the main characters is impressively original.

Ben Tennyson is a teacher in his early 30s. His nine-year marriage to Priya, a broadcaster, is rife with inconsistencies, uncertainties and insecurity. As they lie in bed just after midnight following a stressful dinner party, Ben cogitates while Priya masturbates (a common occurrence).

From the first page the delicate marital balance is tested with a mixture of deep reflections, hasty words and spiteful actions. The question as to whether the partnership can weather the storm of a day that happens to be their son's birthday permeates the book with delicious suspense.

It would have been easy for Vakil to focus on the obvious differences. Priya is originally from India. Ben is a miser while his wife is extravagant. He has a humdrum job; she is a star at the World Service. The list goes on, but while these contribute to the general malaise, readers are left with an overriding sense of how similar their aspirations are along with the futility of them fighting the inevitable.

If the marriage is a struggle of opposites, it is also the opposite of suburban self-satisfaction. While Ben and Priya grapple with themselves and each other, they are also testing their limits as individuals and partners in marital crime. Neither is satisfied with the easy option. Life is too precious to waste on smug acceptance and pointless activity.

During the day, life follows its normal course with reminders about troubled times past. Priya has been unfaithful more than once and her infidelity makes Ben feel small and vengeful. Thus, apparently humdrum incidents such as a difficult interview with a parent at school or leaving a scarf on an underground train stimulate mental replays of previous experiences that have defined their present and point to an indeterminate future. Whacker is their five-year-old son and his birthday party preparations provide a poignant reference point.

Vakil's zesty writing style is engaging. The only voice that lacks verisimilitude is that of Whacker, who sounds like a cross between a dyslexic Bart Simpson and a parrot with a speech impediment. Otherwise, bouncy dialogue is interspersed with tight descriptions and cogent observations. Quotes interspersed throughout the book flirt with the danger of intellectual posturing but manage to fall short of artificial showing-off.

This is a grown-up combination of chick-lit and thoughtful Nick Hornby. It lacks the intensity of the latter and the self-absorption of the former, and manages to find its own voice. Listen carefully: you may just be hearing it again.