Chea Samy was taken into the palace in Phnom Penh in 1925, as a child of six, to begin her training in classical dance. She was chosen after an audition in which thousands of children participated. Her parents were delighted: dance was one of the few means by which a commoner could gain entry into the palace in those days, and to have a child accepted often meant preferment for the whole family.

King Sisowath was in his eighties when she went into palace. He had spent most of his life waiting in the wings, wearing the pinched footwear of a Crown Prince while his half-brother Norodom ruled centre-stage. The two princes held dramatically opposed political views: Norodom was bitterly opposed to the French while Sisowath was a passionate Francophile. It was because of French support that Sisowath was eventually able to succeed to the throne, in preference to his half-brother's innumerable sons.

Something of an eccentric all his life, King Sisowath kept no fixed hours and spent a good deal of his time smoking opium with his sons and advisors. During his visit to France the authorities even improvised a small opium den in his apartments at the Préfecture in Marseille. "Voila!", cried the newspapers, "An opium den in the Préfecture! There's no justice left!" But it was the French who kept the King supplied with opium in Cambodia, and they could hardly do otherwise when he was a state guest in France.

By the time Chea Samy entered the palace in 1925 King Sisowath's behaviour had become erratic in the extreme. He would wander nearly naked around the grounds of the palace, wearing nothing but a kramar, a length of checkered cloth, knotted loosely around his waist. It was Princess Soumphady who was the central figure in the lives of the children of the dance troupe: she was a surrogate mother who tempered the rigours of their training with a good deal of kindly indulgence, making sure they were well fed and clothed.

On King Sisowath's death in 1927, his son Monivong succeeded to the throne and soon the regime in the palace underwent a change. The new king's favourite mistress was a talented dancer called Luk Khun Meak and she now gradually took over Princess Soumphady's role as `the lady in charge of the women.' Meak made use of her influence to introduce several members of her family into the palace. Amongst them were some relatives from a small village in the province of Kompong Thom. One of them - later to become Chea Samy's husband - took a job as a clerk at the palace. He, in turn brought two of his brothers to Phnom Penh. The youngest was a boy of six called Saloth Sar, who was later to take the nom de guerre, Pol Pot.

Chea Samy made a respectful gesture at a picture on the wall behind her and I looked up to find myself transfixed by Luk Khun Meak's stern, frowning gaze. "She was killed by Pol Pot", said Chea Samy, using the generic phrase with which Cambodians refer to the deaths of that time. The distinguished old dancer, mistress of King Monivong, died of starvation after the revolution: one of her daughters was apprehended by the Khmer Rouge while trying to buy rice with a little bit of gold. Her breasts were sliced off and she was left to bleed to death.

"What was Pol Pot like as a boy?" I asked, inevitably.

Chea Samy hesitated for a moment: it was easy to see that she had often been asked the question before and had thought about it at some length. "He was a very good boy", she said at last, emphatically. "In all the years he lived with me, he never gave me any trouble at all."

Then, with a despairing gesture, she said: "I have been married to his brother for fifty years now, and I can tell you that my husband is a good man, a kind man. He doesn't drink, doesn't smoke, has never made trouble between friends, never hit his nephews, never made difficulties for his children..."

She gave up; her hands flipped over in a flutter of bewilderment and fell limp into her lap.

The young Saloth Sar's palace connections ensured places for him at some of the country's better-known schools. Then, in 1949 he was awarded a scholarship, to study electronics in Paris. When he returned to Cambodia, three years later, he began working in secret for the Indochina Communist Party. Neither Chea Samy nor her husband saw much of him and he told them very little of what he was doing. Then in 1963, he disappeared; they learnt later that he had fled into the jungle along with several well-known leftists and Communists. That was the last they heard of Saloth Sar.

In 1975 when the Khmer Rouge seized power, Chea Samy and her husband were evacuated like everyone else. They were sent off to a village of `old people', long-time Khmer Rouge sympathisers and, along with all the other `new people', were made to work in the rice-fields. For the next couple of years there was a complete news blackout and they knew nothing of what had happened and who had come to power: it was a part of the Khmer Rouge's mechanics of terror to deprive the population of knowledge. They first began to hear the words `Pol Pot' in 1978 when the regime tried to create a personality cult around its leader in an attempt to stave off imminent collapse.

Chea Samy was working in a communal kitchen at the time, cooking and washing dishes. Late that year some party workers stuck a poster on the walls of the kitchen: they said it was a picture of their leader, Pol Pot. She knew who it was the moment she set eyes on the picture.

That was how she discovered that the leader of Angkar, the terrifying, inscrutable `Organisation', that ruled over their lives was none other than little Saloth Sar.