Yibin was a very atmospheric town, even in the middle of the Cultural Revolution. The waving rivers and serene hills, and the hazy horizon beyond, produced a sense of eternity in me, and soothed me temporarily from the miseries all around. When dusk fell, the posters and loudspeakers all over the city were obscured, and the unlit back lanes were enveloped in mist, broken only by the flickering of oil lamps seeping through the cracks between the frames of the doors and the windows. From time to time, there was a bright patch: a small food stall was open. There was not much for sale, but there would be a square wooden table on the pavement, with four long narrow benches around it, all dark brown and shiny from years of rubbing and sitting. On the table would be a tiny pea-shaped spark – a lamp that burned rapeseed oil. There was never anyone sitting at these tables chatting, but the owner kept the stall open. In the old days, it would have been crowded with people gossiping and drinking the local 'five-grained liquor," accompanied by marinated beef, soy-stewed pig's tongue, and salt-and-pepper roasted peanuts. The empty stalls evoked for me a Yibin in the days when life had not been completely taken over by politics.

Once out of the back lanes, my ears were assaulted by loudspeakers. For up to eighteen hours a day the town center was a perpetual hubbub of chanting and denouncing. Quite apart from the content, the noise level was unbearable, and I had to develop a technique of forcing myself to hear nothing to preserve my sanity.

One evening in April, a broadcast suddenly caught my attention. A Party Congress had been convened in Peking.

As usual, the Chinese people were not told what this most important assembly of their 'representatives' was actually doing. A new top leadership team was announced. My heart sank as I heard that the new organization of the Cultural Revolution was confirmed.

This Congress, the Ninth, marked the formal establishment of Mao's personal power system. Few senior leaders from the previous Congress, in 1956, had made it to this one. Out of seventeen Politburo members, only four Mao, Lin Biao, Zhou Enlai, and Li Xiannian were still in office. All the rest, apart from those already dead, had been denounced and ousted. Some of these were soon to die.

President Liu Shaoqi, the number-two man at the Eighth Congress, had been under detention since 1967, and was ferociously beaten at denunciation meetings. He was denied medicine for both his long-term illness, diabetes, and his newly caught pneumonia, and was given treatment only when he was on the brink of death because Mme Mao explicitly ordered that he be kept alive so the Ninth Congress would 'have a living target." At the Congress the verdict that he was 'a criminal traitor, enemy agent, and scab in the service of the imperialists, modern revisionists [Russians], and the Kuomintang reactionaries' was read by Zhou Enlai. After the Congress, Liu was allowed to die, in agony.

Marshal Ho Lung, another former Politburo member and a founder of the Communist army, died scarcely two months after the Congress. Because he had wielded power in the army, he was subjected to two and a half years of slow torture, which, he said to his wife, was 'intended to destroy my health so they can murder me without spilling my blood." The torment included allowing him only a small can of water every day during the boiling summer, cutting off all heating during the winter, when the temperature remained well below zero for months on end, and denying him medicine for his diabetes. In the end, he died after a large dose of glucose was administered when his diabetes got worse.

Tao Zhu, the Politburo member who had helped my mother at the start of the Cultural Revolution, was detained under inhuman conditions for nearly three years, which destroyed his health. He was denied proper treatment until his gallbladder cancer was far advanced and Zhou Enlai sanctioned an operation. But the windows in his hospital room were permanently blacked out with newspapers, and his family was not allowed to see him at his deathbed or after his death.

Marshal Peng Dehuai died of the same kind of drawn out torment, which in his case lasted eight years, until 1974. His last request was to see the trees and the daylight outside his newspaper-covered hospital windows, and it was turned down.

These and many similar persecutions were typical of Mao's methods in the Cultural Revolution. Instead of signing death warrants Mao would simply indicate his intentions, and some people would volunteer to carry out the tormenting and improvise the gruesome details. Their methods included mental pressure, physical brutality, and denial of medical care or even the use of medicine to kill. Death caused in this way came to have a special term in Chinese: po-had zhi-si – 'persecuted to death." Mao was fully aware of what was happening, and would encourage the perpetrators by giving his 'silent consent' (mo-xu). This enabled him to get rid of his enemies without attracting blame. The responsibility was inescapably his, but not his alone. The tormentors took some initiative. Mao's subordinates were always on the lookout for ways to please him by anticipating his wishes and, of course, to indulge their own sadistic tendencies.

The horrible details of the persecutions of many top leaders were not revealed until years later. When they came out, they surprised no one in China. We knew all too many similar cases from our own experience.

As I stood in the crowded square listening to the broadcast, the new Central Committee was read out. With dread I waited for the names of the Tings. And there they were – Liu Jie-ting and Zhang Xi-ting. Now I felt there was to be no end to my family's suffering.

Shortly afterward a telegram came saying my grandmother had collapsed and taken to her bed. She had never done anything like this before. Aunt Jun-ying urged me to go home and look after her. Xiao-fang and I took the next train back to Chengdu.

My grandmother was approaching her sixtieth birthday, and her stoicism had at last been conquered by pain. She felt it piercing and moving all over her body, then concentrating in her ears. The doctors at the compound clinic said it might be nerves, and that they had no cure for it except that she should maintain a cheerful mood. I took her to a hospital half an hour's walk from Meteorite Street.

Ensconced in their chauffeur-driven cars, the new holders of power felt little concern for how ordinary people had to live. Buses were not running in Chengdu, as they were not considered vital to the revolution, and pedicabs had been banned, on the grounds that they exploited labor.

My grandmother could not walk because of the intense pain. She had to sit on the luggage rack of a bicycle, with a cushion on it, holding on to the seat. I pushed the bicycle, Xiao-her propped her up, and Xiao-fang sat on the crossbar.

The hospital was still working, thanks to the professionalism and dedication of some of the staff. On its brick walls, I saw huge slogans from their more militant colleagues accusing them of 'using work to suppress revolution' – a standard accusation for people sticking to their jobs. The doctor we saw had twitching eyelids and black rings under her eyes, and I guessed she must be exhausted by the throngs of patients, in addition to the political attacks she was having to endure. The hospital was bursting at the seams with grim-looking men and women, some with bruised faces, others with broken ribs lying on stretchers victims of denunciation meetings.

None of the doctors could diagnose what was wrong with my grandmother. There was no X-ray machine or any other instrument to examine her properly. They were all broken. My grandmother was given various painkillers.

When these failed to work, she was admitted to the hospital. The wards were crowded, the beds jammed right up against each other. Even the corridors were lined with beds. The few nurses rushing from ward to ward could not manage to look after all the patients, so I decided to stay with my grandmother.