The Teotihuacan Enigma (2014)

"For the first time, we are able to show full details of the excavation of a hidden tunnel, sealed and forgotten for 1,800 years, beneath a pyramid in Teotihuacan, Mexico. The ongoing excavation is producing a flood of discoveries that are not only shedding fresh light on the religious and intellectual life of the people who lived here, but also radically changing the way we think civilization began."