The scent of one freshly unearthed white truffle in Barolo was all it took to lead Rowan Jacobsen down a rabbit hole into a world of secretive hunts, misty woods, black-market deals, obsessive chefs, quixotic scientists, muddy dogs, maddening smells, and some of the most memorable meals ever created. Truffles attract dreamers, schemers, and sensualists. People spend years training dogs to find them underground. They plant forests of oaks and wait a decade for truffles to appear. They pay $3,000 a pound to possess them. They turn into quivering puddles in their presence. Why?