Donna Leon's new novel, <b>Blood from a Stone</b>, read by David Colacci, is an audio experience of the highest order. Leon's Commissario Guido Brunetti mystery series never misses, and neither do Colacci's performances. She sets the Venetian scene with unerring strokes, he gives the dialogue and narrative an authentic Italian accent. Brunetti is a dedicated, honest police detective, but his cases are plagued by local corruption. As he investigates the cold-blooded shooting of an African street vendor, despite being warned off by his pompous superior, Brunetti uncovers international entanglements that make everyday corruption seem like child's play. Though categorized as crime fiction, Leon's novels are a genre of their own.