For the first time in human history more than half of us live in cities. Vibrant, complex, colossal - what drives their success? Berlin is a city that never stands still. It's survived invasion, dictatorship, and division. Reunited after the fall of the Berlin Wall in 1989, it is now reinventing itself as a world leader in arts and sciences. In one day in a city in search of its future, we meet the amazing driverless car; the scientists inventing a radical cure for childhood seizures; and unearth one man's private collection of priceless art, stored in a Nazi bunker. Show less