Stan Brock started the nonprofit Remote Area Medical in 1985 to provide medical aid to people in developing countries without access to health care, but as we learn from this artful documentary, the organization now devotes more than half of its resources to helping people in the U.S., many of whom have access to health care but simply can’t afford it. That information is infuriating, but directors Jeff Reichert and Farihah Zaman aren’t out to issue a societal critique; rather, they calmly observe the organization at work over four days, as thousands of volunteers transform the NASCAR speedway in Bristol, Tennessee, into a fully functioning medical clinic, then go about helping the masses of people who show up for treatment. The filmmakers inspire deep admiration for the volunteers, but without reducing the patients to mere victims of our broken welfare system.