S1, E5: At an airport, one simple mistake can mean the loss of millions of dollars, or worse, the loss of lives. At Frankfurt's international airport, everything must go off without a hitch, and for all who work here, they know that failure is not an option. Go behind the scenes and follow the highly specialized employees who repair the engines, screen all the passengers and luggage, change the runway lights, and keep a Mega Airport that uses more electricity than some small countries powered up.