The Past is a Foreign Country, by Gianrico Carofiglio, trans. Howard Curtis

Backed by broadcast media, leisure corporations and even sections of the Government, the British cult of high-stakes poker has sanitised the traditional pastime of spivs and sharks. In these strange times it takes a foreign writer – specifically, a senior Italian law enforcer – to portray the hunger for a killing at the green baize tables in its old-fashioned murky light.

Gianrico Carofiglio is a former anti-Mafia prosecutor from Bari who now advises the Italian parliament on the fight against organised crime. With three accomplished courtroom fictions under his belt, he branches out here into the territory of the psychological, even existential, thriller. The novel that results is a crisp and chilling account of temptation and transgression that fans of Patricia Highsmith will adore.

Giorgio, the narrator, looks back into that "foreign country" of youth when, as a lonely working-class law student in Bari, he fell under the spell of a seductive cheat. Suave, amoral, alluring Francesco leads the awestruck Giorgio into a poker-playing underworld of swanky villas and squalid dives, through illegal all-night sessions where the "endless orgasm" of winning big and often comes at the cost of well-concealed trickery.

To Francesco the backstreet Nietzsche, boasting of his freedom from norms and rules, "it's morally justified to steal from thieves." Giorgio learns to see their victims as "nasty, ugly people" who deserve their fate. Meanwhile, also in Bari, the solitary detective Lieutenant Chiti investigates a series of sadistic sexual assaults...

Giorgio slides inexorably down a slippery slope as parents, girlfriend and studies are left behind. He enjoys the "mindless, shameful elation" of violence when the duo beat up a loser who fails to pay his debts. Soon card-sharping gives way to cocaine-smuggling, and a hallucinatory journey to collect the goods in Spain. Finally, with a viler plan in view, Giorgio cuts loose from his conscience and enters "nightmare country".

Given his career, no reader will come to Carofiglio expecting a tortured moral relativism. Right and wrong never blur, but he does show with sympathy how isolation and insecurity can lead a biddable youngster down into the dark. Pacily translated by Howard Curtis, Carofiglio's writing has a drive and focus that expertly balances suspense and reflection. If his prosecutions begin to match his prose, then the capi of Italian crime have had plenty to worry about of late.

Old Street, £12.99. Order for £11.99 (free p&p) on 0870 079 8897