'China in those days was like a prison and I felt suffocated by it. I didn't even dare dream about not going back, because not to go back in those days would mean to defect and that is so terrifying you know that you would go straight into prison if you are caught. I couldn't think consciously, now this is my chance I'm not going to go back. It happened slowly, over time. I was told that I could stay a little longer, then a little longer. So in the end, when I was told I could stay for good, it was no longer a shock.
Despite never having set foot outside China, and landing in Soho in the late 1978 when hair was big, punk was popular and politics were at the forefront of everybody's mind, Jung felt immediately at home.
'In those days Britain was like another planet, everything was different. But immediately I felt this was a place that I could let my hair down and put my feet up and relax.'
'On my first day out we went to Hyde Park and I just went mad with joy at the sight of the flowers, the trees, the grass. Things that everyone in the Britain took for granted. Mao had banned flowers and greenery in China so all our parks were derelict waste lands with just earth, all vandalised and branches of trees broken off and desolate. It was no longer a crime to cultivate flowers, but there had been no programme to rejuvenate the parks so they lay abandoned. So I just cried when I saw all the green spaces in London.'
The move to London did not allow complete freedom. The students weren't allowed out on their own and had to stay within the strict guidelines set out for them by the Communist Party. Jung smiles, 'We were still made to wear our 'Mao suits' in light blue with Communist badges. We had to move in a group so we were quite a sight in the London streets.
'I was dying to go out on my own so I would find so many opportunities to sneak out on my own - one rule was not to go to an English pub because the Chinese translation for English pub suggested somewhere where indecent with nude women gyrating, so, of course, I was torn with curiosity and sneaked out of the college, darted across the road and went into this pub and saw nothing of the kind, only some old men sitting there drinking beer. I was rather disappointed.'
'One of the last taboos to break was to have a foreign boyfriend because I had come to Britain with a cautionary tale in my head which was that anybody who had a foreign boyfriend would be drugged and put in a jute sack and shipped back to China. I seriously believed this and whenever I was with somebody, even if I was within a mile of the Chinese embassy, my legs would turn into jelly and if I was in a car I would slide under the car window so nobody would see me, it was so ridiculous, that was the first time I used make up because I believed it would provide a satisfactory disguise from the embassy.'
'All the time I was dizzy also with fear in case somebody saw me or I met somebody Chinese who would denounce me to the embassy. I thought everybody was a spy and that every Chinese looking person was from mainland China. But of course in those days there wasn't anybody from mainland china in the UK and there were no spies.'
It took Jung a long time to stop feeling scared. Years passed before she could sleep properly and she has said that the publishing of Wild Swans in 1992 was when she finally got rid of the fear that had haunted her. Meeting Jon Halliday, the eminent Russian historian, who later became her husband, was an important step towards her rehabilitation. Together the pair have built their life in the UK, settling into the West End of London, and have spent twelve years collaborating on the new book, Mao: The Unknown Story.
'I had no idea it would be a 12-year project when we started. I thought it would perhaps be three years because I thought I knew Mao and would simply be filling in the gaps in my knowledge. I knew his adult history, but we didn't know what he was like as a child, for example, or why he had become the man he was. It soon turned out that I knew nothing, everything was lies.
'My husband and I divided our work by language. I'm Chinese so I worked on the Chinese language sources. He speaks many, many languages so he was landed with the rest of the world. He spent many hours in the Russian archives which turned out to be a treasure trove. Before we wrote this book I had no idea that Russia was going to be on virtually every page of our book. I had no idea of the importance of Stalin and Khrushchev and Russia in Mao's life and in Chinese history but it turned out that it was vitally important.
'Even though Mao was a difficult subject, so personal, the journey of discovering his life was huge fun. My husband and I were like a pair of detectives trying to solve one mystery after another, trying to get into the head of Mao and understand him, that's such great fun. We delved into well-known historical events like the Long March, like the war with Japan, like China's relationship with Britain over Hong Kong and we realised they were not at all as the myth had them to be and we were finding out new things and we were giving out new interpretations to the events. That's just tremendous fun.
'We were extraordinarily lucky in our timing because when we were doing the research many of Mao's contemporaries were still alive. We also had access to the Russian archives that were opened in 1990 during the Yeltsin years. Many of them are closed again now, so we just caught that window of opportunity.
'I miss our research - talking to important historical figures such as Mao's interpreters with Stalin, Henry Kissinger, Edward Heath about his meetings with Mao, Mao's mistresses, his family, the Communist leaders around the world all historical figures. The research is fascinating.'
The book was published in 2005 to mixed reviews. Many - perhaps most - were ecstatic: The Times called it �a triumph that exposes its subject as probably the most disgusting of the bloody troika of 20thcentury tyrant messiahs in terms of character, deeds and number of victims. This is the first intimate political biography of the greatest monster of them all, The Red Emperor of China.'
But some attacked the book. Professor Thomas Bernstein of Columbia University referred to the book as '... a major disaster for the contemporary China field...' because the 'scholarship is put at the service of thoroughly destroying Mao's reputation. The result is an equally stupendous number of quotations out of context, distortion of facts and omission of much of what makes Mao a complex, contradictory, and multi-sided leader.' As a retort, Jung and Halliday released a statement: 'The academics' views on Mao and Chinese history cited represent received wisdom of which we were well aware while writing our biography of Mao. We came to our own conclusions and interpretations of events through a decade's research.'
Jung is philosophical about the criticism - and the praise. She says, 'I did have hopes about how the book would be received and it is more or less what I expected. Some people are just stuck with the idea that Mao was 70 per cent good and 30 per cent bad or vice versa - they wanted to believe that he wasn't pure evil, that he wasn't on the same level as Hitler or Stalin. Of course he was. In America we were giving a talk at the Asia Society on Park Avenue and there were people outside handing out leaflets about our book who were crazy Mao-ists and a man gave me a leaflet and said are you going to the lecture, this is what you really should know. I took the leaflet and I said I'm the one giving the lecture and he was really rather taken aback,' she laughs.'
The book is still banned in China, as it is Wild Swans, but slowly the two tomes (sitting at 992 and 720 pages) have sneaked their way in to the still closed society. The book is published in Hong Kong (although officially a part of China, the island is in practice, a very separate society) and many copies have been sneaked on to the mainland. People download the books, get relatives to send copies. 'Last time I was in China,' Jung says, 'there were pirate copies for sale. I was delighted.'
Jung goes back to China regularly now. She has never been banned, despite her writing, because, she thinks, she has never sought a public voice in the country. Her books are not mentioned in the press, she is not quoted, she doesn't appear on TV and she doesn't try to. The government leave her alone and she doesn't talk.
'China is changing, it has been slowly, for years. People will now criticise the government in a very bold way, in a taxi cab or in a restaurant. But funnily, they are far more reluctant to say a bad word about Mao, who is long gone and dead. His legacy of fear has not gone away.'
Other elements of Mao's terrifying reign have disappeared, Jung confirms, returning to when flowers were banned in China.
'In the early 1980's I saw the first flower market open and that was such an emotional moment for me because I love flowers and grass and when I was a child I felt very sad having to remove the grass from the school lawn. Suddenly there were people coming to this flower market on their bicycles and they had these bunches of flowers, not cultivated flowers, it really was more like wild flowers on their bicycle bars and some flowers sticking out of the baskets and on the luggage rack. I was almost in tears with joy.'
The reason for Jung's regular return visits is her mother, who still lives in the Sichuan Province. 'We did get her out when Wild Swans was first translated into Chinese in case she got into trouble because of it, but as it happened it was all very calm, so she went home and has been living there and nobody has molested her. That's a real sign that China has changed enormously from Mao's time, that they won't penalise my mother for a book I wrote.
'When I was writing Wild Swans, I didn't think about whether it could be a success or not - I never imagined then that it would be translated into 32 different languages and be one of the best-selling non-fiction books ever. I just worried what my mother would say, because she had played a big role in writing the book. Then one day I got a letter - my mother can always anticipate my anxiety - and said 'the book might not do well, people might not pay attention to it, but you are not to worry because writing the book has brought us closer together and she said that for her, that was enough, I had made her a happy woman.' That was it, for me. I didn't care if the book did well, it had fulfilled a goal. Everything else was a bonus.'