Is a documentary an information-delivery system or a work of art? This question keeps dogging the makers of nonfiction films, and director Margaret Brown takes a stab at having it both ways in The Great Invisible. Brown, who made the affecting 2004 portrait Be Here to Love Me: A Film About Townes Van Zandt, has here tackled the Deepwater Horizon oil spill—and most important, its aftermath. Brown does due diligence in reminding us of the devastating 2010 explosion at the offshore oil rig, which killed 11 workers and caused extensive damage to the ecosystem of that part of the Gulf of Mexico. One of the film’s eeriest tools is home-movie footage shot on the rig before the disaster, a cheerful tour through the state-of-the-art (but still dangerous) structure.