In the highlands of Papua New Guinea, a strange illness begins devastating entire communities. Victims start stumbling. Their hands shake. Their speech becomes slurred. Some develop emotional changes or inappropriate laughter. Eventually they lose the ability to walk, eat, and care for themselves. And then they die. There is no fever. No obvious infection. No known poison. Even stranger, women and children are dying far more often than adult men. Kuru had reached epidemic proportions by the time researchers began systematically investigating it in 1957, with roughly 1,000 deaths were documented in the first 5 years.