Finding Vivian Maier, which runs at Cinematheque this week, is about art, the art world, and the life of one artist. But at its heart, this fascinating documentary is a mystery story.

Since 2010, Vivian Maier has been revealed—posthumously—as one of the great street photographers of the 20th century. The Chicago-based Maier took over 100,000 photographs in her lifetime, only to hide them away in trunks and boxes. In 2007, one of these boxes was randomly acquired by John Maloof, a young real estate agent and flea-market fan.

'Maier’s works show an original eye and an unerring feel for the perfect emotional moment.' - Alison Gillmor

Maloof managed to track down information about Maier only after her death in 2009, and he began picking up more of her hoarded belongings, including random objects, old receipts and letters, and thousands and thousands of her photographic works (including prints, negatives, and rolls of unprocessed film). Maloof was drawn at first by Maier’s absolutely striking photographs, but he soon became equally intrigued by her enigmatic life.

In this 2013 documentary, which played at last year’s Toronto International Film Festival, Maloof and filmmaking partner Charlie Siskel pursue the elusive Maier through images, interviews and investigations.

Maier’s works show an original eye and an unerring feel for the perfect emotional moment. They offer a vivid sense of the social history of postwar Chicago, from swanky shopping areas to the stockyards, from society women to skid-row down-and-outs. As a photographer, Maier feels tremendous empathy for her subjects, but she also stands at a self-protecting distance.

Maier is, as one of the film’s subjects declares, “paradoxical.” Following up on Maier’s multiple addresses, Maloof discovered that she had been a nanny, working for families in Chicago’s affluent suburbs. A prickly, secretive, solitary woman, Maier lived on the edges of other peoples’ lives, obsessively documenting the world around her with a Rolleiflex box camera. 

The film’s narrative is well-paced and suspenseful, as Maier’s complex personality slowly comes into partial focus. The essential mystery—why she compulsively took photos but never shared them—remains intact. One of the interview subjects suggests that the intensely private Maier “would have hated all of this,” meaning the film, as well as her sudden flash of fame.   

And Maloof’s motives are admittedly murky. He is sincerely devoted to Maier’s art, and he seems to recognize a kindred spirit, being a bit of a hoarder himself. But he is also an opportunist, using this exploration of Maier’s mystique to generate even more interest in work he now owns. When he complains about major art institutions being reluctant to endorse Maier, even as audiences all over the world are embracing her, there is an obvious conflict of interest.

Still, if the treasure hunter is flawed, the treasure is an incredible find. It’s a good thing that Maier’s astonishing work is being seen. Maybe it’s also a good thing that Maier herself is still hidden, despite Maloof’s best efforts to uncover her.

Finding Vivian Maier plays at Cinematheque April 17 - 29 and April 23.