They turned out of the city centre and went north, climbing the long drag into the big housing estate. The name of the estate was familiar, from the local television, but she had never been there. Nothing urgent in the information they gave her, no passion, but the figures were beyond her comprehension. A worldwide trade in narcotics with a profit margin of 100 billion American dollars. Seizures and disruption of trafficking into UK the last year of?1.45 billion, and what was seized and disrupted, on a good day, was one in five shipments and, on a bad day, was one in ten.

Ken said, 'But they're the super-glory figures, we don't operate at that level. We work down here in the gutter, where the skag and the rock ends up. Down here a kilo of heroin, skag, goes for thirty grand, street price. Crack cocaine, rock, means?7,500 sterling, cheaper because of saturation. Out there in the big world they're talking thousands of kilos, tonnes – we're little people, we're talking kilos and grammes.' She listened…

Brent said, 'You being a teacher, Miss Parsons, you'd be good at arithmetic. Ten grammes doesn't give a big long high, ten minutes' worth for an habitual, but it costs, my sums, seventy-five quid, and it's addictive, so you get to need a lot of grammes, and that means you need a lot of cash, and you steal, fight, burgle, maybe kill, for the cash.'

She saw tower blocks of homes, and terraces of homes, and she saw the children, like the ones that she taught, running in dog packs. She thought she saw a poverty and a despair… She saw an old man hurrying, limping, heavy on a stick, and his face was frightened and she wondered whether he had?75 sterling in his wallet. She saw an old woman scuttling with a shopping bag towards the dark entrance of a tower block, and she wondered whether the old woman had?75 sterling in her purse, or in the tin under her bed, or folded into her pension book and hidden, and she wondered how many old men and old women needed to be robbed to make a crack cocaine high that lasted ten minutes. She felt sick.