The doctors flying in from elsewhere wouldn’t begin seeing patients until Friday, but people began lining up Tuesday, camping out for medical care they couldn’t get otherwise. Over the course of three days, nearly 2,000 patients got basic needs taken care of—rotten teeth pulled, prescription glasses made, high blood pressure diagnosed—thanks to volunteer labor at a massive temporary health clinic. Naturally, this all happened last spring in the wealthiest nation in the history of the world.

Remote Area Medical, directed by Jeff Reichert and Farihah Zaman, tells the story of a weekend encampment at the Bristol Motor Speedway in eastern Tennessee in April 2012 by Remote Area Medical, a nonprofit group founded in 1985 with an eye to providing care for impoverished residents of far-flung countries around the globe. But “overwhelmed with the need here,” as its founder tells the camera, RAM now makes 60 percent of its expeditions in the U.S., allowing people without insurance or money to pay for check-ups a rare chance to get medical help. (One 61-year-old man with skyrocketing blood pressure says during his examination that it was his first visit to the doctor since he was a teenager.)

The film looks at the daunting logistics involved in setting up what’s essentially a mobile hospital at a NASCAR track, but the directors spend far more of their time with the patients than the doctors or organizers. Some of them hopeful for what the treatments will bring, some ashamed of taking charity medicine, many a mix of both, their stories make for an infuriating critique of a health-care system and an economy that blithely leaves so many of our fellow citizens behind. The matter-of-fact approach the patients take to explaining why they’re lined up at the track and why they need the help is far more powerful than Michael Moore-style bombast would be. “We don’t have jobs,” one woman says. “And the jobs that are here aren’t paying living wages.” Which means, ultimately, that if they want to see the dentist, they don’t have much choice but to sleep in their cars for two nights.