NOVA Secrets of the Sky Tombs airs on WSKG-TV January 4, 2017 at 9pm. A team of scientists and explorers probe high altitude caves in the Tibetan Himalayas looking for clues to how humans found their way into this forbidding landscape and adapted their bodies to survive. Along the way they discover evidence of ritual burials, thousands of years old: skeletons, mummies, and evidence of practices designed to ward off ancient vampires and even zombies. The towering Himalayas were among the last places on Earth that humanity settled. Scaling sheer cliff sides, a team of daring scientists hunts for clues to how ancient people found their way into this forbidding landscape and adapted to survive the high altitude.