A photojournalist who came to Calcutta in the late ’90s to document Sonagachi, its red-light district, Zana Briski eventually befriended many of the local prostitutes’ children. She gave them cameras and taught them how to shoot and edit the world they knew: the crowded, filthy boarding house where their mothers live and toil. In Briski and Ross Kauffman’s tough, thoroughly engrossing film (winner of this year’s documentary Oscar), we meet the ebullient Puja, who ventures fearlessly into Calcutta’s streets to snap candids; Avijit, who coordinates offhanded (and one-handed) cool-guy camera moves with an impeccable eye for the perfect shot; and Suchitra, a shy, tall beauty who’s reached the dangerous age of 14, when many girls ‘join the line’. For this self-selecting group of bright, energetic, curious kids, the only path out of the brothels leads to a decent boarding school, and Briski sees their photography as a means to fund their education. (Amnesty used the Sonagachi children’s pictures for a 2002 calendar.) The spectre of long odds and narrow choices shades every frame, yet the tone is often buoyant and legitimately inspirational, as when the class runs riot during a seaside field trip, or when Briski hacks her way through a bureaucratic no-man’s-land of red tape and somehow emerges with a passport for Avijit (who’s selected to attend a World Press Photo Foundation event in Amsterdam). ‘Born Into Brothels’ testifies to the kids’ untaught resilience and hope, and to their mentor’s selfless energy. Inevitably a documentary of this stripe risks aestheticising poverty but here it’s the kids themselves who compose the most arresting images.