Obviously cyclist Lance Armstrong felt in full possession of his superhuman powers when he turned to filmmaker Alex Gibney to document his post-cancer comeback in 2009. Gibney, honoured for his investigative films about Enron and US-condoned torture in the Middle East, took on a feel-good assignment for a change. He was rewarded with something close to total, exclusive access. Though the doping allegations were already flying, he was persuaded that Armstrong was on the level, and that his story of triumphant perseverance was one worth capturing in detail. Fortunately for Gibney the truth finally overtook Armstrong before the feel-good film was finished. In the film that eventually emerged, disillusionment lends Gibney’s familiar curiosity about power and corruption a personal edge. His interrogation of Armstrong and the world that he dominated delivers an assessment that is, to quote the Village Voice, “wholly necessary, brilliantly executed, and a complete bummer”. Thanks to the unsurpassed access to the racers that he was granted in 2009, the hero’s disgrace is wrapped up in as intense and up-close a filmed account of the Tour de France as you are ever likely to see.