michel tournaye says he's brought home some slices from his dinners out, and studied them under a microscopeme to check their origin. tournaye has tried to blow the whistle on the restaurants that sell chinese truffles at french prices, but the police have more important matters on their plate and rarely do anything about it. 28 tons of chinese truffles come into france every year. where do they go? >> bruno: i think i know where they go, but i'm not going to tell you. >> stahl: if you tell me, you're in trouble-- is what you're saying? they'll hurt you? >> bruno: everybody is in danger in this business. >> stahl: so we began to look for chinese truffles ourselves. we found this product that is exported to the u-s. on the front of the can, it says "black winter truffles; product of france," while on the back, in small print, it says "tuber indicum," the latin name for chinese truffles. ♪ ♪ when we showed one of the cans to the urbanis at a kitchen at their headquarters, it seemed to ruin their lunch. >> urbani: this makes us crazy. this destroys all the tradition of the truffle. it's an enti