The Skill episode explores the push and pull of Nature versus Nurture in the development of elite athletes.

Executive produced by Alex Gibney, Enhanced explores the race to the edge of human performance.

Elite athletes know the line between glory and bitter disappointment is razor thin - a millimeter or nanosecond can put you on, or keep you off, the podium. In this episode, we explore the mental training techniques deployed by professional athletes.

This episode delves into the history of the crackdown on steroids, which in turn, created a cat-and-mouse game between athlete and enforcer that has failed to ensure a level playing field.

What are the limits of the human body? One man, the mad scientist of distance running, is determined to find out.

Athletes have learned to hack their bodies, and become bigger, stronger, faster. But the one thing they can't escape is injuries, and the need for recovery.