IT WAS, he said, the greatest revolution the world had ever seen. It would be written in golden letters on the pages of history: how the Cambodian people had returned to the countryside to become pure, agrarian communists, relieved of all private property, free of all ties of family, religion and culture, devoted only to Angkar ("the organisation") and the teachings of Mao and Stalin. When Ieng Sary, then deputy prime minister and foreign minister for the Khmer Rouge regime, sent out such messages in 1975 to thousands of Cambodian students and intellectuals living overseas, they naturally came home - to be condemned as spies, thrown in jail, tortured and killed. Few survived his propaganda. There were, Ieng Sary admitted - disarming Western listeners with his ready, radiant smile, as he savoured a sip of champagne - a few technical hitches along the revolutionary way. For example, the regime had to remove everyone from Cambodia's cities, because there was not enough transport to bring in food for them. It made more sense to take the people to the countryside, where the food was. What he did not add was that these "new people," once in the fields, became slave labour, forced into punishing manual work and so underfed that they tried to survive on grass; and that over the four years of Khmer Rouge rule perhaps 2m Cambodians, or around a quarter of the population, died from overwork, malnutrition and starvation, as well as mass killings. If you faced Ieng Sary with this, he shrugged his shoulders. What did he know? As the foreign minister, he had to travel all the time. He was just a secondary figure, not privy to the policies and tactics of Pol Pot, the regime's "sole and supreme architect," as he called him. For himself, he had killed one man - no more - and done nothing wrong. He was a gentle person, he insisted, as he sniffed delicately at the bottles of French perfume he liked to buy on first-class international flights. What he did not add, though most people knew it, was that Pol Pot was his chum from the elite Lycée Sisowath in Phnom Penh and his student buddy at the Sciences Po in Paris, later his brother-in-law when they married girls who were sisters. Deep down, Ieng Sary thought him a simpleton. He would bang on his door at dawn in the Latin Quarter, yelling at him to get to his Marxist studies, long before they both began, in 1963, to stir up revolts in the Cambodian countryside against the American-backed regime. Once they had seized power in 1975 Ieng Sary was "Brother No. 3," implicated with cosy, family closeness in the torture of thousands in secret prisons and afterwards in their murder. As foreign minister his role was hypocritical, yet simple. He had to present a disarming face to the world, build up visceral hatred of neighbouring Vietnam and draw in help from China, the regime's only friend, in the form of money, weapons and advisers. When the Khmer Rouge government itself was toppled by a Vietnamese invasion in 1979, he fled to Thailand; and there found fresh clothes, new sandals and a VIP air ticket to Beijing, all supplied by the Chinese embassy in Bangkok. His skilful contacts with China kept the movement going for two more decades. Sapphires in his hands You could say he was a proper revolutionary, in drab jacket, cap and scarf, railing against "economic saboteurs" who wasted food and "traitors," undoubtedly CIA or KGB agents, who smoked Western cigarettes or had non-Cambodian blood. Yet he had been born in loathed Vietnam (his old Vietnamese name swapped for a Cambodian nom de guerre) to a Chinese mother and a rich father, and had become the very model of a hated French-speaking intellectual. Despite all that, slippery as an eel, he triumphantly survived inside the regime. He was also increasingly rich. The peasant-poverty enjoined by the Khmers Rouges, and practised by some, never appealed to him. In 1982 (the movement still pretending to govern Cambodia from bases on the Thai border) he gave up the job of foreign minister to become minister of economics and finance, which required China's largesse of more than $1 billion to flow through his hands. He made deals, too, with Thai sapphire-mining and logging companies. The rough frontier town of Pailin became his bailiwick, containing his large villa and bungalows, each with a tank parked outside, for his supporters. In 1996, sensing change in the wind, he persuaded thousands of Khmer Rouge troops to defect from Pol Pot, leave the jungle and claim an amnesty from the prime minister, Hun Sen, and King Sihanouk - a man to whom he had always bowed, while feeling nothing but contempt for him. Life was good after the amnesty, as indeed it had always been for him before it. His Toyota Land Cruiser, with its darkened windows, was a common sight outside the capital's best restaurants. Security guards protected his villa in an elegant part of town. He smoked the best cigars. There was the nettlesome matter of a UN-backed Cambodia tribunal investigating war crimes, which arrested him in 2007 and put him on trial four years later. But it had convicted only one person, and moved so achingly slowly that it was never going to catch him. He waited to frustrate it with his charming, duplicitous smile. Crimes against humanity? Moi?