Alex Gibney directs this documentary exploring the controversial career of American cyclist Lance Armstrong. Gibney followed Armstrong, a seven-time Tour de France champion, on his return to racing in 2009. Armstrong's goal in returning was to defy persistent allegations that his past victories were in part due to doping, but in 2012 he was handed a lifetime ban from cycling after being found guilty of taking performance-enhancing drugs, something he finally admitted in 2013. The documentary includes interviews with Armstrong, who offers his side of the story, as well as contributions from cycling contemporaries and those who follow the sport.