Wildlife photographer Geng Dong has braved perilous terrain and freezing temperatures across the Tibetan Plateau in search of his subject - the beautiful, yet elusive, snow leopard.

Mostly active after dark, these big cats have great eyesight and choose to seek shelter among rocks or caves during daylight. This behavior has earned them the nickname "mountain hermits" among scientists, who can only study them with the help of sensitive infrared cameras.

Geng, on the other hand, has braved the frigid cold for hours, days, and sometimes weeks at a time, poised to capture a photograph of these beautiful animals.

Although it is a "game of luck", as he is first to admit, Geng has been rewarded for his patience and endurance with pictures of both lone snow leopards and cubs in the shadow of their watchful mothers - an enviable experience for any wildlife photographer.

Yet his presence can sometimes be a threat to the snow leopard. Once, when he was photographing a mother and her two cubs, he realized something was wrong. Spooked by his presence, the cubs had fled from their mother - and the longer he stayed, the more dangerous it became for the cubs, as the mountains were full of predators.

"At that moment, my pictures were less important than ensuring a family reunion," Geng said.

After codirecting the TV documentary series Snow Leopard, which won numerous national awards, Geng turned his camera to the animal's life on the Tibetan Plateau, "to give locals more exposure to the animal and its conservation."

This new documentary is the result of four years of hard work, with Geng traveling to the Qinghai-Tibetan Plateau dozens of times, developing strong relationships with wildlife conservation groups and scientists engaged in tracking, studying and photographing the snow leopard.

His crew have had to camp out in the bleak terrain for weeks at a time, enduring icy winds, altitude sickness and snow blindness as they covered more than 40,000 km in Qinghai province alone during the film period, from 2011 to 2015.

Along the way, Geng has acted as director, photographer and producer, dealing with the project's many headaches and money woes.

Yet despite the hardships he never gave up, inspired by the area's residents who "have much harder lives than ours".

Geng said the documentary also profiles wildlife conservation and the relationship between snow leopards and the local community, which he described as "the core of the story".

Take Sori, who herds a flock of 240 sheep and a few dozen yak. He has struggled to protect his animals from snow leopards that stalk the plateau and once, almost at tipping point after losing a number of animals, took aim at one of these "hated cats" with his firearm, Geng explained.

Though the snow leopard was in his sights, Sori did not squeeze the trigger because he saw a cub nearby, which reminded him of his own children.

Geng was moved by this relationship between the people and wild animals on "the roof of the world", as the plateau is known, which he said can be partly attributed to the influence of Tibetan Buddhism.

"Many shepherds have no idea of environment protection, but they understand the Buddhist teaching that all living beings should be cherished," he said.

Another story that left an impression on Geng concerned the Buddhist monk Drukgyab, who chooses to live in the wilderness rather than at a temple.

Known for his pioneering environmental protection work, the monk persuades locals not to hunt animals and is often one of the first to spot snow leopards in the wild.

"He protects snow leopards from hunters because he believes the animal is weak," Geng said.

"When he drives the snow leopard away from sheep, it is because he thinks the sheep are weak. He cannot bear to see life wasted."

Animal conservation is a trickle-down business. If big animals are protected then so too are thousands of other species, and by association water resources, said He Bing, a project officer of leading wildlife conservation NGO Shanshui.

However, little is known about the elusive snow leopard, its numbers or distribution.

Mainly found in Central Asia, it is estimated that there are only about 2,000 left in the wild in China.

Climate change, poaching, urbanization and pasture expansion are the animal's biggest threats, according to He.

"The destiny of snow leopards is the destiny of all creatures in the world," said Zhou Bing, chief director of the documentary.

For Geng, he just hopes that his footage will raise awareness of the snow leopard's plight.

"Some say that there is not enough of the snow leopard in my documentary, but I don't mind. I just hope my work can make people aware of the animal and its fight for survival," he said.