How to find a lost, ancient Mesoamerican city

Steve Elkins is a filmmaker and, above all, an explorer. Flying over the rainforest with lidar technology, he found an ancient city—complete with pyramids and plazas—and put together a team of scientists, filmmakers and journalists to explore and document the site. We talk to Elkins and journalist Doug Preston about the film and the book, both titled “The Lost City of the Monkey God.”