In the remote northwest of China an epic adventure is unfolding before the cameras, the true story of a young Englishman who led a school of young Chinese children over the mountains to safety from the advancing Japanese army in the bitter winter of 1944.

The film, The Children of Huang Shi , began life as a brief newspaper story and will have taken 22 years to reach the screen by the time you see it next autumn. That has to be one of the longest gestation periods — even by Hollywood standards. For example, the movie Rain Man , starring Dustin Hoff-man and Tom Cruise, took eight years from first draft to first night.

The painful birth of the film, now being made with an Alist director and leading man, is almost as strange as the story it tells: that of an English innocent abroad who by chance carves his place into the history of the three-sided war in China in the 1940s involving Mao’s Communists, Chiang Kai Shek’s nationalists and the invading Japanese army.

George Hogg was just 23 when he arrived in Shanghai for a two-day visit in 1937. Fresh out of Oxford, he was on a round-the-world trip before taking a job in banking, but never returned home. Seven years later he was dead, having woven a story of courage and high adventure into a brief life that is still remembered in China today.

There are many ironies in Hogg’s story. A quintessential middle-class, rugger-playing Oxford graduate taking time out before starting a career in the City becomes a hero almost by chance in the Chinese war of liberation.

His achievement would have remained unknown at home but for a snatch of conversation half-overheard in a Beijing bar.

The bar was in the British Embassy Club and it was there in August 1985 that I overheard a junior diplomat complaining bitterly that he had to fly to the remote town of Shandon on the Mongolian border, where a statue had been put up in memory of an Englishman called George Hogg, who had died in 1944.

Having flown out from London as holiday relief for The Daily Telegraph ’s Beijing correspondent only days earlier, I was no China expert; but I knew enough to realise that the Chinese did not lightly erect statues to foreigners. I also knew I needed a story. News was thin and I hadn’t filed for two days.

No one in the embassy had heard of Hogg but a small article in the People’s Daily the next day pointed me to the one man alive who had worked with him and known him well.

Rewi Alley was a New Zealander who had clung to the Maoist cause throughout the chaos of the Cultural Revolution. I found him in an old tenement building on the outskirts of the city. Then in his late eighties, he spoke for hours about Hogg, describing him as “an outstanding young Englishman who fell in love with a foreign people and devoted his life to their betterment. What he did made him deeply and widely loved.”

I had my story. I telexed the piece over, received an overnight reply from the foreign desk saying “Hogg double top”, which meant I had a reasonable show in the paper - and forgot it. A week later I got a call from Barry Spikings, the well-known Hollywood producer who had won a raft of awards for The Deerhunter . The story had been picked up by the Los Angeles Times . He was the first in a long cast of producers, agents and directors who fell in love with the Hogg story . . . but never got round to making the film. Spikings flew to London, poured me large quantities of champagne in Mark’s Club in Mayfair and gave me the name of Linda Seifert. “The best script agent either side of the Atlantic,” he opined.

If George Hogg is the true hero of the film then Linda should be its heroine. She did not believe that a journalist could begin to write a film but she did, and still does, believe that Hogg’s extraordinary story will make a great film. She gave me a pile of old scripts and a book on screen-writing. I presented a first draft three weeks later. The title was The Bitter Sea, from an old Chinese saying.

Linda was a hard task-mistress. She made me write the script again and again. Each new draft came back with a demand for a rewrite. Finally the script was sent out and the rewrites began again as production companies paid for options and demanded their own version.

Needless to say, nothing of my script - not even the original title - has survived four different writers and the many film companies that have developed the film over the years. What has survived is Hogg’s story, a wartime odyssey that is now being filmed in a $17 million (£8.6 million) independent production. Roger Spottiswoode, who made the Bond film Tomorrow Never Dies , directs and the rising star Jonathan Rhys Meyers plays the lead.

The film will no doubt stir memories in China, where Hogg’s reputation is still kept alive by the loyalty of his surviving old boys - all now in their eighties. But I doubt it will make much of the dramatic trajectory of Hogg’s life that took him within a few months from a privileged existence at Oxford to life on the run from the Japanese secret police in China.

While living rough in northwest China he recalled his days at Wadham College, where he took a second in modern greats, in a letter home.

“Rugger, beer in silver tankards, honeyed muffins for tea, white flannels and music in punts on the river, bump suppers, champagne, bonfires of lavatory seats, reading about the fall of Addis Ababa in front of the common room fire and surprise on learning that a double blue was a necessary qualification for a top colonial post.”

This was the world that Hogg left behind when he set sail on the Queen Mary in 1937 to New York on the first leg of his round-the-world journey. Having hitchhiked across the US he joined his aunt, Muriel Lester, a well-known pacifist, for the voyage to Tokyo. Aunt Muriel was determined to give the Japanese the benefit of her views on militarism. Disliking such posturing almost as much as he did the Japanese, Hogg decided on a weekend trip to Shanghai. He arrived in January 1938 just as the Japanese took control of the city.

It was a dark and violent world in which he found himself. The Japanese had embarked on a deliberate policy of civilian mass murder as they expanded into the interior from their control of the coastal belt and the capital, Beijing. Aided by appeasement policies in Europe the long-cherished Japanese ambition to subjugate China was becoming reality.

The savagery of the conflict caused huge casualties and by the time of the Communist takeover in China in 1948 it is estimated that 13 million had died in a decade of war.

Hogg flung himself into this maelstrom. He became a stringer for the Associated Press in Shanghai, was expelled by the Japanese to Tokyo, and made his way back to northern China and Beijing via Korea.

In Beijing hemet Kathleen Hall, a New Zealand nurse whose mission clinic had been destroyed by the Japa- nese; she was smuggling food and medicines from the occupied capital to guerrillas in the countryside. Hogg joined these risky sorties for a while and then, under increasing scrutiny from the Japanese police, the two of them made a nighttime escape to the liberated areas late in 1938.

Delayed for months by typhus, when Miss Hall saved his life through diligent nursing, Hogg finally linked up with Mao’s eighth route army in Yenan. By this stage he had learnt accentless Mandarin and had developed a deep interest in the emerging cooperative movement in free China.

There was no question of a military role for the new arrival. He had no training and in any event the Communists did not welcome foreigners in their ranks, with the exception of Soviet pilots.

Hogg cut a strange enough figure as it was. Rewi Alley described him at the time as “a happy broad-shouldered young giant in a shirt, shorts and sandals with the bearing of a forward in a rugby pack”.

In letters home to his parents, who lived in Harp-enden, Hertforshire, Hogg described a life of high adventure as he crisscrossed northwest China helping the cooperative movement with which he had become an “ocean secretary” — the traditional designation in Mandarin for a foreigner of his status.

One week was spent at the headquarters of General Nieh, the commander of the guerrilla armies in the Shansi border region. Hogg described long steam baths with the general and other Communist luminaries discussing the tourist prospects for North China after the war. Neither the English adventurer nor the Red Army generals seem to have appreciated what Mao had in store for the country.

At other times Hogg slipped through Japanese occupied cities at night and dodged ambushes by day. Conditions in both the liberated and occupied areas of China were terrible. From 1939 the Japanese had launched the infamous “three all” campaign — kill all, burn all, destroy all.

A girlfriend, Chiang Chih Esia, joined him briefly in his travels but, wounded in an ambush, she died of blood poisoning on a makeshift operating table. Hogg was remorseful at having taken the girl from her family and exposed her to danger, but continued his endless travels through what he called “a countryside full of the dead, the dying and the wounded”.

Finally at Shuangshipu, a small village set at a crossroads in the Tsingling mountains in the north-central Shensi province, Hogg found his real calling in China.

There in 1943 he was appointed headmaster of a school for technical apprentices who were being trained to bolster the cooperative movement. Eight headmasters, all foreigners, had failed to prevail over the unruly mix of illiterate peasant children from the north and west, and the sons of rich families who had been driven from the coastal areas by the advancing Japanese.

Hogg succeeded by imposing sound English public-school rules. The boys were made to rise at dawn and swim in icy rivers, rubbing in sulphur ointment afterwards to rid themselves of scabies and lice.

In his own words, Hogg managed to “smelt this varied human material into a real community without the help of any past school tradition and with no school spirit”. It was an extraordinary achievement, but a greater challenge lay ahead. The Japanese were advancing west and Hogg took the decision to move the entire school to the safety of Shandon, a hilltop town in a corridor between Mongolia and Tibet.

This was a risky decision. Shandon was 700 miles away and the journey would cross 12,000ft to 16,000ft mountain ranges. Although most of the boys were teenagers, some were very young. Winter had already set in. Hogg scrounged a fleet of carts, pulled by five mules each, piled them high with 15 tons of equipment — boys, books, machinery and food — and set off early in the new year of 1945.

It was an appalling journey made by foot, mule cart and finally by six ancient lorries in what proved to be the coldest winter in 20 years. Several mules and carts went over the edges of ravines but only two boys were lost in the ten-week journey. One died of a heart attack and the other turned back on his own.

At the regional capital of Lanchow, a staging post on the old Silk Road to the West, Hogg swapped his mule cart for trucks. He was halfway to the sanctuary of Shandon. The headmaster finally led his exhausted and half-starved schoolchildren to an old Buddhist temple near the town in March 1945.

Four months later, having rebuilt the school, Hogg cut his foot, probably playing basketball with his pupils. He developed tetanus and lockjaw set in. While couriers raced back to Lanchow to find serum, the boys did their best for their headmaster. They knocked his teeth out one by one to feed him soup through straws.

The late Professor Brian Harland, a geologist and fellow of Caius College, Cam-bridge, was prospecting in the region and met Hogg a few days before his death.

Harland said: “He was in excruciating pain but stayed cheerful to the end. The boys sang all the school’s songs to him as he died. The carpentry section stayed up all night making him a wooden coffin.”

Hogg was buried on July 22, 1945, the day after he died. His will was simply: “My all to the school.”

A bust of Hogg, restored after the desecration of the Cultural Revolution, stands in the school at Shandon. The school’s Silk Road Library, which was built in his memory, is filled with books. His headstone over a grave near by carries lines from his favourite poem by Julian Grenfell:

And life is colour and warmth and light

And a striving evermore for these;

And he is dead who will not fight;

And who dies fighting has increase.

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