If great runners are born, not made, what roles do training and technology play? Will cutting-edge engineering and chemistry create vehicles that move faster than previously thought possible? This program presents a quest to understand speed in all its manifestations. Viewers get a look at the North American Eagle, an automobile that’s more fighter jet than car, designed to challenge the world land speed record. At the Walthamstow dog track in east London, the program shows how greyhounds, the second fastest land animals on earth, are built for velocity. And a sprint on a 60km/hour treadmill uncovers the secrets of track runners—revealing that speed isn’t about how fast you move your feet. (23 minutes)