He was ashamed that he had shouted at his grandson, but the tension was always bad when they were within sight of shore and had a package on board.

The trail started in the foothills of northern Afghanistan.

Far into remote mountains, in little irrigated fields, farmers grew the poppies and were the first to take the cut; it was subsistence farming, and without the poppy crop they would have starved. For the farmers, the recent American-led invasion of their country had been a gift from God: their previous rulers had reduced, on pain of death, the growing and harvesting of the poppies, but now no government writ reached them.

It was a slow-moving trail. Eighteen months from start to end. At first the journey took the poppy seeds to market for haggling and argument, then buying. As opium, the product travelled in caravans of lorries, camel trains or in pouches on mules, north out of Afghanistan. It reached the old Spice Route, half a millennium old, and in Dushanbe, Samarkand or Bokhara Customs men, warlords and politicians took more cuts. The price was beginning to ratchet.

Then, on to Turkey, the nexus point of the trade, where the laboratories waited to render opium into raw heroin. Ten kilograms of opium made one kilogram of heroin. More cuts, more profits to be taken from the farmers' labour. Turkey was only a staging point, not a place of consumption.

Europe was the target. Each year, the craving for and addiction of Europeans to heroin demanded a supply of an estimated eighty tonnes. Turkish gangs took it on. Across the Bosphorus or by ferry over the Black Sea and a landing in mainland Europe. Up into the war-ravaged Balkans and more division of the product made in Belgrade or Sarajevo, and the price kept climbing as more men took their share of the profits. When wads of dollar bills were passed, the lorries drove unsearched through international boundaries. On into the Netherlands and Germany.