For the first time in human history more than half of us live in cities. Vibrant, complex, colossal - what drives their success? New York - anchored by a strip of land only 13 miles long and 3 miles wide - has somehow become one of the most important cities in the world. It's the distilled essence of the land of opportunity. In one day we meet the 27-year old from Kyrgystan who's revolutionizing online fashion; visit the subterranean world that keeps the city cool; and go onstage with one of Broadway's newest sensations.