Shot entirely on location in the Mongolian steppes, Desert Dreams is written and directed by Zhang Lu, a Chinese film-maker of Korean descent. He takes on the story of a mother and son who escape from North Korea and journey to Mongolia. There they encounter a man battling desertification by planting trees.

With North Korea a political hot potato, Desert Dreams may seem topical but Zhang describes it as a story about humanity, regardless of nationality - about men and women, mothers and children.

"I had the image of a mother who takes her son on a long journey," he says. "But this story starts after they've reached Mongolia. It's about how they communicate and live with the people there."

Inspired by stories he heard in China about North Koreans making their way to Mongolia, Zhang wrote the script after visiting Mongolia last year.

Originally a novelist in China and a professor of Chinese literature, Zhang premiered his first short, Eleven, in competition at the Venice Film Festival in 2001. His feature debut, Tang Shi, screened at the Locarno festival and his second feature, Grain In Ear, was shown in Cannes' 2005 Critics' Week.

Laurent Danielou, managing director of Paris-based sales agent Rezo Films International, says: "We've been following [Zhang] since Cannes two years ago. Zhang is a talented director and we are very happy to have Desert Dreams."

"Back then, we only knew to make a film, not what it is to sell it," remarks Zhang. "We weren't prepared for the market."

Desert Dreams, which screened in competition at this year's Berlin film festival, shot for 28 days in July and August 2005, but Zhang and his Korean/Mongolian crew were on location for two months.

"All the equipment broke down because of the sand winds, and everyone got sick except for me," he says. "At night, wolves would come by to watch. At first we were scared, but they would just watch quietly and leave - they didn't eat us.

"Korean crews need to take a day off for every week they work, but I only had to ask one thing, 'Do you want to go back to Korea as quickly as possible'' And they would work full time. They couldn't run away if they wanted - you could leave the camp but there'd be nothing but wolves."

Korean actress Suh Jung (The Isle, Green Chair) plays the mother, and veteran Mongolian actor-director Osor Bat-ulzii (Words From The Heart) plays the conservationist.

The $1.3m film was produced by G21M Inc, which put up around $620,000 of the budget. The Korean Film Council (Kofic) provided $430,000, and France's CNC granted $130,000. StarEast Digital Lab in Korea also provided about $106,000 worth of digital intermediary and film development work.

Desert Dreams
A mother and son escape from North Korea to Mongolia, where they meet a conservationist
Budget: $1.3m
Production company: G21M Inc (S Korea)
Co-producers: Jiij Production (Mongolia), Arizona Films (France)
Main cast: Suh Jung, Osor Bat-ulzii
Int'l sales: Rezo Films International