Producer Sally Ingleton was developing a film about an art program that assisted Tibetan refugees to overcome the trauma of leaving their homeland when she heard about an incident on the infamous 6000-metre Nangpa Pass, an ancient trade route from Tibet to Nepal. It was October 2006, a few weeks after a savage attack on unarmed Tibetan refugees by Chinese border police, which resulted in the death of a 17-year-old nun a few hundred metres from the Nepalese border.
The events were witnessed by numerous mountain climbers, one of whom had filmed the attack. Many of the refugees had managed to avoid arrest and made it safely to Kathmandu. After securing finance to develop a script, Ingleton teamed up with director Mark Gould, who had previously filmed in the Himalaya and had a strong interest in the subject. The pair set to work tracing key participants in the drama—the Tibetan refugees who survived the attack, the climbers who witnessed it, the climbing companies that operate in the region and the shadowy illegal guides who orchestrate refugee crossings.