Kolkata has been seen through many lenses, but this one takes the viewer into the dark heart of the city. Filmmaker Phil Cox's new documentary, The Bengali Detective, examines the interior life of this fascinating city by following in the footsteps of a Bollywood obsessed, dance-crazy private detective called Rajeshji.

In 1998, Cox set up an indie production company, Native Voice Films, which has grown into a globetrotting, truth-seeking collective of filmmakers of assorted nationality and journalistic proclivity. Their output varies from quality broadcast and independent documentaries to NGO work and conflict reportage for leading news organisations. Their roll call includes films (many award-winning ) on the Sudan civil war, motorbike vigilantes in Venezuela, state-enabled social silos in Rio, unemployment in Osaka, survival stories of the Guarani Indians of Argentina and a close-up of the Camorra mafia in Naples. They've also paid attention to India, with films like Kashmir Rising about civilian ferment and Orissa Women Vs The Mines that documents tribal opposition to illegal mining. "We've made many films in India, " says Cox. "Most have been serious political and social commentary films, but some were also experimental. " The Bengali Detective was one such. "In Kolkata I came across the phenomenon of the Private Detective, and realised this could be a window into middle-class India, " Cox says. A series of auditions threw up Rajeshji, a real-life dance hound, whose gritty day job was leavened by his Bollywood moves afterhours. "Usually we came up with rather dull ex-military men who ran detective agencies. I wanted to find an 'Everyman' who could connect with the audience and who had qualities that would allow me to mix the Bollywood and verite styles. " Incredibly, after a hard day's work, Rajesh would steer his team to instant stress relief through Bollywood dance. Cox's crew realised that Rajesh's propensity for dance had to be shown working up to something substantive. "We couldn't just show the group dancing randomly, " says Sounak Chakravarty, the film's editor.

"We found a clever way to insinuate his dancing into the documentary by encouraging him to apply for a slot on 'Dance Bangla Dance', a TV reality show. "

Cox partially descended on a detective story because he was fascinated by a society that had come to increasingly rely on shadow crime-busting when an often indifferent police force couldn't help. The detective would be a catalyst. "He was the window into the lives of the clients whom I wanted the audience to come to know and empathise with. The film was always to be about the client's dilemmas as much as the detective himself, " writes Cox. These "dilemmas" included a triple murder, suspected adultery and counterfeited goods, and Rajesh solved two of those three in the span of the film. The docu turned out to be a sleeper hit, and when it went out on HBO at the end of 2011, it had some of the highest audience ratings for a foreign documentary. To protect the identity of the people investigated, the film will not be screened in India, although Internet sites will throw up trailers.

Another Native Voice film that may, however, be available for viewing by the end of the year is titled The Auction House And The Secret Life of Objects, about the last existing auction house in India - The Russell Exchange. "I was doing some production work on The Bengali Detective while looking for an idea in the city for a film of my own. Eventually, I came across The Russell Exchange and Anwer, the owner. A quick cup of tea later, listening to some of his stories, the film was born, " says Ed Owles, the Native filmmaker who made this one.

It was ideal, for objects arriving here to be bought and sold were each witness to the human condition. "It's bursting with stories and layers, a place where people meet to laugh, argue and trade, " declares Owles, whose background in anthropology and personal interest in what objects can mean to people is what drew him naturally to the auction house. "The objects seemed to be a visual route into peoples' lives, ranging, for example, from an ivory draughtsman's set to the 8 mm camera used for 1960s holiday videos by an Air India pilot. "

Owles - whose documentaries have taken him from the Libyan Desert to the oil rigs of the North Sea - comments on documentary as a form of journalism. "Documentary often brings more nuance to a situation than traditional journalism. It seems to offer more than the news agenda. " Cox believes the empathetic documentary fills a space in a saturated information age where a deeper truth can be reached. He says, "The portrayals of Hugo Chavez, for example, are seen either as saviour or devil, depending on what one reads. We want to put in the realities of living in Venezuela. People are pulled along by very human instincts of survival. Kashmir's authorities, like Venezuela's, try to control the media, and that is when we have to find deeper ways to reach what we're after. And that can entail anything - leaping fences in the night, travelling with rebel forces, hiding a camera in a cake or simply walking in with an official stamp. "