Cordyceps sinensis (in Tibetan, Yartsa-gunbu) has been called “Tibet’s golden worm” and “The Viagra of the Himalayas.” When it was discovered 30 years ago as a natural remedy, it became a boon to Tibetan nomads. Today, some nomadic Tibetan communities bring in as much as 80% of their income collecting it. Yartsa Rinpoche follows Darlo, an elder in the Amdo region, who with his family forms a group of 30 that treks 800 kilometers to collect the “worm,” while exploring its larger implications.