For the first time in human history more than half of us live in cities. Vibrant, complex, colossal - what drives their success? Moscow is the largest city in Europe. It has endured wars, revolutions and drastic social change. It is home to more billionaires than any other city in the world. In one day in a city where anything is possible we meet the artist who spent 20 years underground; the cosmonaut who's spent more than a year of his life in space; and get an exclusive peak behind the scenes of the Bolshoi ballet. Show less