And I realised that I had seen this kind of confession before in dozens of interview rooms and holding cells. They deny everything until it can no longer possibly be denied. But when the truth is finally so close that you can smell it, taste it, feel it in the back of your throat – then you can’t shut them up.

‘Stephen was – how can I put it? – a trifle squeamish,’ he began. ‘He liked to play the hard man out there in the Essex nightlife, but the lorry with those girls in Chinatown – well, it put the wind up him.’

Put the wind up him. Meaning to cause extreme fear. It was an expression that his own father might have used.

‘My son wanted to see you and confess,’ Warboys said. ‘Which would have been good for his conscience but bad for my long-term plans.’ He was suddenly exasperated. ‘But I’m a businessman. You have to understand. I never wanted to hurt anyone.’

‘Then why are so many young women dying?’

‘Supply and demand,’ he sighed. ‘Market forces. We just had all these women coming in that we didn’t need. We didn’t have any use for them. They were no good to us. They were surplus to requirements. I had all the staff I could possibly use. But once the pipeline was open and flowing, it was impossible to turn it off. You can’t imagine the logistics, Detective – talent scouts at nursing colleges, reliable drivers for the journey across Europe, the odd anarchist to ease our way across borders. There were deliveries that were never even collected.’

‘Is that what happened to Hana Novak? A delivery that nobody collected?’

The name was unknown to him.

‘Who’s Hana Novak?’ he said.

I felt myself shaking with rage.

‘Hana Novak died in that lorry we found in Chinatown. She wanted to be a nurse.’

He laughed shortly.

‘Do you know how many qualified nurses there are in the world who want to come to this country? It’s rather a lot. And even when I attempted to shut off the pipeline, and told that tattooed freak in Grande-Synthe that we didn’t need any more, there were still all these women arriving. And then that old bag contacted me. My father’s favourite whore.’

‘Madam Theresa.’