A great metropolis has been discovered, buried beneath the pastures of the Danube. Archaeologists claim that the lost city of Carnuntum was a place where men trained, fought, and died as gladiators. Through excavations and high-tech research using ultra-high resolution cameras and scanners, we reconstruct this ancient civilization from the Roman Empire. See what life was like 2,000 years ago, in this megacity and in the arenas, where slaves, prisoners, and volunteers fought to the death before roaring crowds.