Black diamond - Martin Walker

France's Prigord region is the home of the exquisite black truffle, and at five thousand euros a kilo, it's a treasured local asset. When reports come in that this unique delicacy is being adulterated with a cheaper Chinese version, Bruno is asked to investigate the scam.

In St Denis market, a Vietnamese family runs a popular stall selling their country's dishes, until one day their stall is overturned and wrecked by attackers who look Chinese. Bruno wonders if these are the opening shots of a Viet-Chinese triad war.

When brutal murder is added to the mix, Bruno has his work cut out to find the connection between present and long buried crimes that are linked to France's colonial past.

Martin Walker spins an intriguing mystery leavened with charm and humour, informed by a deep love of French rural life and a broad knowledge of France, past and present. It is a combination that will win him many devoted readers.