It says a good deal about the modern art world that a caption in the final credits of Heather Lenz’s “Kusama: Infinity” notes that a painting by the Japanese artist that a fellow named Frank Stella purchased for $75 when she was struggling to be recognized in New York recently sold for $750,000. That kind of rise from obscurity to fame is hardly unique among artists, of course, but as Lenz’s visually elegant, emotionally engaging documentary makes clear, in Yayoi Kusama’s case it was a particularly long and difficult climb.

Lenz’s film is conventional, but expertly so. It smoothly weaves together archival materials, interview excerpts and voluptuous shots of the artwork to sketch Kusama’s troubled life, from a childhood in Japan marked by dissension between her parents and an effort by her mother to stifle her artistic inclinations, through the flamboyantly attention-seeking “happenings” of her American stay and the mental problems that have plagued her, to her late-in-life rediscovery and popularity.

Lenz handles the roller-coaster ride with aplomb, obviously enjoying, for example, the proto-feminist episode in which the young Kusama wrote to Georgia O’Keeffe asking her advice and then followed up by moving to New York City, where she struggled to gain recognition during the sixties, sometimes by trying to manipulate people to her purposes, and led provocative episodes of performance art to protest the Vietnam War and espouse other progressive causes. Lenz also appreciatively covers Kusama’s presence at the Venice Biennale in 1966, where she exhibited a garden of mirrored globes that she offered to sell to passing customers for a mere $2 apiece—until the organizers ended the stunt.

But the film does not overlook the mental traumas that troubled Kusama over the years, resulting in at least one suicide attempt. She returned to Japan in 1973, where she remained in relative obscurity for nearly two decades, living in a mental hospital, until a revival of interest in her work in the late eighties led to retrospectives, honors—and enormous popular success.

Throughout Lenz sprinkles excerpts from interviews—with gallery and museum officials, supporters and fans, as well as the octogenarian artist herself—into the chronological narrative, which she illustrates with photos and footage, but especially Kusama’s work. The subtitle, of course, comes from Kusama’s signature mirrored infinity rooms, but the visuals pay no less attention to the omnipresent polka dots that have been a constant from the earliest days in Japan.

The film closes by returning to Kusama’s hometown of Matsumoto, where she had once been treated as a pariah because of what was considered her scandalous behavior, her name even removed from a school graduation list. Now she is thought of as a local hero, her work serving as an incentive for young people to nurture their talents. That’s another way in which Lenz emphasizes how Kusama has finally found acceptance and admiration after a lifetime of difficulties and setbacks.

When all is said and done, of course, it is the art that matters, and the documentary presents it in all its vivid glory: kudos are due to Lenz’s technical associates—especially cinematographer Hart Perry and editor Keita Ideno—in that connection. Allyson Newman’s score is also an asset. But one can’t divorce the artist from the art, and Lenz gives proper due to both.

It doesn’t hurt, of course, that some of Kusama’s work has fetched extraordinarily high sums in recent years—indeed, one piece sold for the highest price ever paid for a work by a living female artist—more than seven million dollars. That even dwarfs the sale price of Frank Stella’s painting, though one shouldn’t complain of a profit of 10,000%.

Some would question whether Kusama’s paintings and installations are worthy of the praise—and prices—they have received. That debate will undoubtedly continue, bit what’s undeniable is that Heather Lenz has crafted a portrait that celebrates her as a person as well as an artist.