Venice, Italy is a city in crisis, and it took dangerous, cutting-edge engineering to build it. As apocalyptic floodwaters unleash havoc, experts use the latest tech and modern-day science to reveal if building it a second time would be just as deadly.

The Roman Empire built some of the greatest structures in history, and now, experts use cutting-edge technology to see if these cutting-edge engineering marvels could be made today. This is a mashup of S01E07, "Fortress of the Gods" and S01E03, "Ghosts of the Colosseum."