This month's book: You Shall Know Our Velocity, by Dave Eggers

We know that Dave Eggers' first novel will break most of the rules of conventional fiction from its opening sentence. It tells us that the narrator has died, along with his mother, "in a burning ferry in the cool tannin-tinted Guaviare River in east-central Colombia". So this posthumous tale signals from the off that tragedy and remembrance will stay close to its heart.

The rule-smashing continues. Will and his friend Hand (thought and action: two obviously emblematic names) decide to blow a $38,000 windfall that Will has picked up by acting as a model for a lightbulb logo. We see a drawing of the logo, as well as other maps, photos and diagrams throughout You Shall Know Our Velocity. Do such devices add to the book's substance, or merely serve as amusing gimmicks?

The pair intend to travel around the world in a week and give all the cash away. So a Kerouac-style update of the wanderings in On the Road joins an accelerated postmodern twist on the plot of Around the World in Eighty Days. Will, as narrator, is shadowed by bereavement and disaster. His best mate Jack has died in a car accident, and Will himself has survived a beating that Hand may have provoked.

Their philanthropic jaunt becomes a search for purpose and redemption, fuelled by the easy-come-easy-go affluence of young Americans. How far does this subjective quest turn into a global fable of riches and poverty?

Nothing about the trip goes according to plan. They begin, almost by chance, in Senegal, and journey on a crazy zigzag path through Morocco, England, Estonia, Latvia and Mexico. The world, or rather those odd neutral locations of airport, taxi, bar and hotel that travellers mostly experience, proves something of a let-down. Yet most long-haul voyaging feels much more like this than like the sanitised progress recounted in the glossy travel magazines. Is Eggers the idiosyncratic loner also a kind of hyper-realist, who bravely tells it like it us?

Will and Hand find precious few deserving takers for their money, and plenty of rip-off merchants. Another touch of allegory? All the same, moments of generosity, respect and mutual recognition break through the smart surface. In style, You Shall Know Our Velocity recalls the freewheeling informality of Eggers' cult memoir, A Heartbreaking Work of Staggering Genius. Along with the shaggy-dog-story atmosphere, however, goes a virtuosity that propels him into delirious prose riffs. They remind you of his affinity with indie rock bands. Is this fiction in the traditional sense, or a new form of semi-autobiographical performance art?

Underneath all the grandstanding and ingenuity, the bedrock of loss and grief remains. Compass-free travel and scattergun charity, as we knew already, will never heal the emotional wounds acquired back home. Might this personal narrative of feckless but damaged US youth and its impact on the world have a political dimension? Or does this picaresque romp simply amount to a quest for individual salvation?

Penguin, £7.99 (350pp)