‘Billy was still in uniform when I met him,’ I said. ‘And there were people who didn’t think he would make it because he was kind and decent. But these were the things that made him a great policeman. He was the bravest young man I ever met. Not because he was never afraid but because he always did the right thing, no matter how scared he was. Every day of his working life, he brushed up against the worst of people – cruel, violent men with all their lies and greed. And he saw people who were hurt and scared, innocent people, good people. In most of us, that leaves a hardness, but not Billy. He was not lessened by it as most of us are. He remained himself.’ I shook my head at Mrs Greene and Siobhan. ‘And I don’t know what else to tell you.’

‘But you got them,’ Mrs Greene said.

I remembered Madam Theresa when they dragged her out from behind the recycling bins in the basement of the Hopewell Centre. And I saw Troy twitching as his lifeblood ebbed from him on the floor of that room with the empty bath and the single bed. And I also recalled how they ran, all of them, the clients and the women and the hired hands, how they couldn’t get away from the penthouse of the Hopewell Centre fast enough.

‘Yes,’ I said. ‘And it wouldn’t have happened without Billy.’

There was a fierce pride in the face of Mrs Greene. But the fiancée was still poleaxed by the loss of all their plans.

‘I don’t understand,’ she said. ‘I still don’t understand why Billy died.’

‘Billy lost his life helping us to smash a people-trafficking network that was run out of the Grand-Synthe refugee camp in Dunkirk,’ I said. ‘Illegally bringing vulnerable young women into this country to work in the sex industry.’ I thought of Rabia Demir, full of a killer dose of Fentanyl. ‘It is quite likely that murder charges will result from our investigation.’

She shook her head, as if my words were meaningless.

And they were.

Because I knew what she was really asking but I had no answer.

Was it worth it?

We had our tea and cake, and my left elbow throbbed like a beating heart where Troy had hit me with his hammer and we were not in that room for more than thirty minutes for there is never much that can be said.

‘Billy’s fiancée – Siobhan – will meet someone else,’ Edie said when we were back in the car.

‘I hope so,’ I said. ‘What is she? Twenty-three? She should meet someone else, shouldn’t she?’