Shining a light into the shadowy world of China's stolen children

Jezza Neumann was production manager on an award-winning exposé of Beijing's orphanages. Now he has gone undercover to direct its follow-up. By Ian Burrell

Not a bad effort for a first attempt: Jezza Neumann's debut as a documentary director has been put forward for an Oscar by HBO and given star billing by Channel 4, which has assigned almost two hours of tonight's prime-time schedule to his shocking undercover exposé of the black-market trade in Chinese children. The film has so angered China's government that it has attempted to prevent broadcast.

During three and half months posing as a tourist and working alongside a small, hand-picked team of sympathetic Chinese journalists, Neumann managed to outwit agents from China's Public Security Bureau and obtain interviews with parents who have had children abducted or who have felt forced to sell their offspring in order to avoid being punished under laws designed to manage the population.

The film-maker befriended a maverick retired detective, accompanying him to rescue a 16-year-old girl from a country brothel, and filmed one of the child-traffickers trying to justify his actions. Each piece of precious footage was smuggled out of China and brought back for editing at True Vision, Neumann's independent production company in a suburban west London house by the Thames.

The result of this elaborate project, which has been two-and-a-half years in preparation, is China's Stolen Children, a 105-minute special for C4's Dispatches, giving a remarkably complete account of how babies are bought and sold in the world's most populated nation.

Narrated by Sir Ben Kingsley, the documentary has been recommended for an Academy Award by the American channel HBO, which part-funded the venture. The film picks up the story of a previous award-winning True Vision production, 1995's The Dying Rooms, in which the investigative journalists Brian Woods and Kate Blewett uncovered the scandal of China's state-owned orphanages, where victims of the country's one-child policy were abandoned.

Neumann, who has been with True Vision for 13 years and began his television career as a runner, was a production manager on that project. China's Stolen Children has enabled him to show that he can make documentaries in his own right: "For me it was stepping out from the shadow of Brian and Kate, who I have learned so much from, and saying 'Look, I can make films as well...'", he says.

China has of course changed a great deal since 1995, including in its awareness of the activities of foreign-based journalists. Neumann was especially aware of the potential risks of making a film in defiance of local authorities, having been a former colleague of James Miller, the British film-maker shot dead by an Israeli soldier while filming in Gaza in 2003.

"I was thinking of James when making this film. I always admired what he did and the fact that he worked outside his comfort zone," says Neumann. He says that the biggest danger he faced in China was deportation. "The real risk was faced by my Chinese team who were facing prison sentences."

Ahead of hosting the Olympic Games next year, China is anxious to avoid damaging publicity, as demonstrated by the Chinese embassy's attempts to obtain an injunction to prevent Channel 4's airing of the programme. Before travelling to China last year, Neumann drew up a long list of security protocols designed to identify every possible eventuality and hamper efforts by security officials to infiltrate the project. Contacts were never called using the same SIM card twice. When the film crew were apart they were required to send coded text messages back to C4 commissioning editor Mark Roberts in London at 10am each day. The crew referred to each other by codenames – the researchers were Piggy and Panda, the cameraman was Heeha, and Neumann was Bob.

Neumann became sophisticated in anti-surveillance methods; arriving by circuitous routes to meet contacts in parks and cafés or pulling up outside homes under cover of darkness in order to avoid the men in suits and dark glasses. "It sounds corny but it's what you watch in the movies," he says. "Normally they try to make it obvious you are being followed because they want to frighten you. They cannot really arrest you just for talking to people, they know they have got the Olympics coming up."

But more startling than the cloak and dagger methods and the exhausting logistical demands (Neumann had to meet one set of parents by leaving his rural hotel at 4am, driving for four hours across rough terrain and then hiking across hills for an hour), the remarkable thing about the film is the testimony of the interviewees.

At the heart of the story is Chen Jie, a boy who was kidnapped from his family at the age of five while he was being looked after by his grandmother. Neumann, who has a son almost exactly the same age as Chen Jie, explores the torment of the parents as they consider having another child, effectively admitting that their boy will never return.

He also locates a young woman of 19, pregnant by her 21-year-old partner, and facing a fine under a law that says she must be 20 to bear a child. Worse, she is advised by her doctor that, having had a previous termination, it would not be safe for her to abort the pregnancy. The couple decide to have their baby. And immediately give it up.

Neumann films them meeting a child trafficker who explains that, despite the preference for boys (who have a value of around £700), girls also have worth (around £250), especially if the parents do not try to place them in a wealthy household. Affluent buyers have a strong bargaining position. "The trafficker says that if you want your baby to go to a family in a rich area you won't get as much money as if you sell to a poorer family."

Astonishingly, Wang Li, the trafficker, also maintains that he is merely providing a service to couples in need.

"He says he is an introduction agent. As far as he is concerned he's not doing anything wrong – he's just helping people."

The film-maker also tracks down a police officer turned private eye, Detective Zhu, who has become one of the few figures of hope for the parents of abducted children. With his Chinese assistant producer Sky Zeh, Neumann accompanies Zhu to a country brothel north of Chengdu, where they snatch to safety a 16-year-old girl who had been forced into prostitution.

After 14 weeks working inside the child trafficking trade, while simultaneously posing as a tourist, Neumann returned to Britain to edit the film with Woods and Blewett. He hopes that it may force a rethink of the one-child policy, which he believes is the cause of the gender imbalance which means that 40 million Chinese men are without a partner.

The Chinese response to Neumann's findings has so far been defensive, accusing the film of being superficial. "The trend of gender imbalance among the newly-born is a question that calls for scientific study and careful redressing," it said in a statement. "Finger-pointing is simply not the way forward."

Neumann has kept a diary of his adventure which may later be turned into a book. Chen Jie, meanwhile, who is due to celebrate his seventh birthday next month, is still missing.

'China's Stolen Children' will be shown on Channel 4 tonight at 9pm