Documentary of a secret photographer
17 April 2014 Last updated at 01:43 BST
A new documentary called Finding Vivian Maier tries to uncover the truth behind the reclusive life of a Chicago nanny who secretly took well over 100,000 photographs during her life.
Some of Vivian Maier's photos are are now viewed as masterpieces.
The film has been co-directed by Chicago native John Maloof who bought a trove of her negatives at an auction in 2007 with no knowledge of Maier or her talents.
Talking Movies' Tom Brook reports.