Could shrunken heads from the Amazon hold the key to curing cancer? One man thought so—and spent a lifetime trying to prove it.

It’s the biggest environmental lawsuit in history. The people of Lago Agrio, an oil-rich area in the Ecuadorean Amazon, are suing Chevron for $6 billion after decades of spills. The case has been underway since 1993.

On a press junket in Ecuador, the author investigates the ethics of shopping.