There once was a man who won the world’s toughest athletic contest seven times in a row, and also beat cancer, and presided invincibly over a vast empire of splashy fundraiser bracelets. He had some help from drugs, which means there’s a story here about the human condition as a function of pharmacology, but documentary ace Alex Gibney prefers a study of personalities. Here he’s got several to choose from. There’s Lance Armstrong, of course, the one-time superhero of competitive cycling who now is banned from it for life. And there’s the small army of Armstrong’s various abettors, detractors, rivals, and inquisitors — including Gibney himself, who’d been working on a boosterish documentary called The Road Back, but, what with the big confession about doping and all, had to rework it as The Armstrong Lie. That narrative course change, from comeback to comedown, gives the film its juice, and Gibney knows it. He had unprecedented resources for gathering actual, rather elaborate Tour de France footage, but a better sense of his own personal production values comes through in the emphasis suggested by bracketing the film with Armstrong’s Oprah-exclusive mea culpa. Obviously a driven and prideful man, Armstrong is a true competitor, all right: riding aggressively, answering accusations vindictively, apologizing incompletely. As for the historical record of his legacy, Gibney’s doc makes a good first draft.