Vivian Maier (1926 - 2009) was an American street photographer. She worked for forty years as a nanny in Chicago, Illinois. During those years, she took over 150,000 photographs, primarily of people and cityscapes in Chicago. Her photographs remained unknown and mostly undeveloped until they were discovered after her death in 2009. In 2013 the BBC made a reconstruction of her life and work. An amazing story.