A team of experts are cramped in an underground chamber with a network of mysterious tunnels leading from it. It’s a stone-built subterranean labyrinth in the Peruvian Andes, created more than 3,000 years ago by a lost civilization. The scientists launch a four-wheeled mini-robot with a camera and lights down one of the narrow passages, which is too small for a human to enter. And what the high-tech machine reveals is both macabre and deeply shocking.