You may have heard of Dolly Parton's Imagination Library, but it's unlikely you know its impressive history, scope, and impact, as detailed in the tidy little documentary The Library That Dolly Built. And because it revolves around Parton, who has honed humble glamour to an art, it's an infomercial that will make you feel better about the world — a worthwhile mission in the depths of 2020.

It's called a "library" but it's really a service: The nonprofit Parton set up sends a book a month to any eligible child who signs up, from birth to age 5 — more than 1.3 million books a month — on the theory that parents will read them aloud to the kids. The result is parent-child bonding, early reading interest, and, eventually, a shelf full of beloved stories.

It's been around for 25 years now, reaches all 50 states and some foreign nations, and insists on local involvement in every community it serves. (Eligibility is based on location, not income.) It's hard not to be impressed, but the documentary, directed by University of Tennessee media professor Nick Geidner, lets the interview subjects and the facts speak for themselves, no hype added. Geidner includes lots of parents and children from across the nation in the story, as well as interviewing some of the selected books' authors, so it's not all education insiders — although even the "experts" in the film seem as folksy as Parton herself, perhaps because a lot of them come from east Tennessee.

Parton makes a few appearances — as one person observes, "Dolly provides the pixie dust" — and Geidner include a picture-book's worth of Dolly bio as well — for example, making the point that Whitney Houston's megahit with Parton's "I Will Always Love You" was a huge boon to the Library's funding. In a documentary season chock full of consequential conspiracies, crimes, and disasters, The Library That Dolly Built may be slim, but it's a pleasure to be immersed in untarnished goodness for an hour or so.

Grade: B-plus. Available to stream via FineArtsTheatre.com.

(Photo: Dolly Parton’s Imagination Library)