Investigative journalist Mark Daly, is a keen athlete but for more than a year he had embedded himself into the murky world of doping in athletics. It’s an investigation like none he has done before, having to push himself to his physical limit in order to truly understand the world he’s entering, he even goes as far as becoming a doper himself.

The story includes tales of coverup and hypocrisy, that have spanned some 30 years and include a few of the biggest names in sport, such as a British olympic legend. Daly asks do the cheats themselves still retain the upper hand in their ability to avoid detection?