Watch Cities of the Underworld Season 2 Episode 3 Online

Tokyo, Japan is a city straight out of the future, above ground... and below. We'll go beneath the busy streets to see the latest technology that will save the city from the many natural disasters ready to strike. From there, we head back in time to World War II to see how Hiroshima's underground offered protection from the most powerful bombs... and get an inside look at the secret life of the Ninja. Don Wildman hosts.