Blood Rain by Michael Dibdin

After his last case, among the gentle hills and lush vineyards of Piedmont, Inspector Zen finally receives the order he has been dreading all his professional life: his next posting is to Sicily. And indeed it soon turns out that he will need all his cunning and skill to survive in a milieu where unwritten rules are enforced with ruthless violence, one false step can prove fatal, and the truth must be paid for in blood.

The gruesome discovery of an unidentified, decomposed corpse sealed in a railway wagon on a disused siding marks the beginning of Zen's most difficult and dangerous case. Set against the backdrop of the three-thousand-year-old city of Catania, in the shadow of the smouldering volcano of Etna, Blood Rain reveals Aurelio Zen at his most desperate and driven.