Filmmaker Nicholas D. Wrathall shot this documentary portrait of the celebrated author and political firebrand shortly before Vidal died in 2012, and he couldn’t have asked for a more striking scene than the one in which the writer shows him the grave he plans to occupy (beside his longtime companion, Howard Austen, who died in 2003). This offers a standard chronological tour of Vidal’s colorful career, incorporating lively TV footage (the famous onscreen clashes with William F. Buckley and Norman Mailer), commentary from a handful of notables (Mikhail Gorbachev, Christopher Hitchens, Tim Robbins, Dick Cavett), and, perhaps best of all, onscreen bon mots from the master (“Love is a fan club with only two fans”). What Hitchens describes as Vidal’s “conspiracy theory of history” shapes the political story, which touches on both Vidal’s epic historical novels and his insurgent campaigns for elected office. “Whenever I want to know what the United States is up to,” Vidal remarks at one point, “I look into my own black heart.”