‘You need to come with us, Detective Chappell,’ Drummond said, and as he proceeded to caution her she turned to me and her face seemed to fold in on itself.

I thought she might ask what was going on, to brazen it out, but she didn’t and for me that confirmed her guilt. She probably knew that it wouldn’t take us long to substantiate the claims that Slack had made in his note. He’d stitched her up because even those corrupt coppers on his payroll were his enemies, and he hated them with a vengeance.

‘How could you, Kate?’ I said. ‘What you did was despicable.’

Tears exploded at the corners of her eyes and a hot flush infused her face.

‘I’m so very sorry,’ she sobbed. ‘I swear I didn’t know he was going to do what he did. That’s the truth.’

The tears streaked down her cheeks but I had no sympathy for her.

‘You gave Slack our names and addresses,’ I said. ‘And you stayed silent when the killings began. That makes you an accessory to murder. I hope you spend the rest of your life in prison.’

They were the last words I spoke to her. But as she was led away I stared at her back, my eyes burning holes in the air. And I wondered how she had managed to fool us so well, and for so long.

Several other detectives witnessed what had just happened, including Janet Dean, who stepped up to me and said, ‘Well, for the life of me I never saw that one coming. This has been one hell of a week for surprises.’

I looked at Janet and felt a shiver of guilt for believing that she and not Kate had been the bad apple on the team.

74

Rosa

She was humming a tune to herself as she got dressed. She felt deliriously happy, and the last thing she wanted to do was go out and kill someone else.

She would have preferred to spend another day with Alice. They could have stayed in bed, or gone for a walk, or just sat on the sofa and talked about their future together.

But it wasn’t possible, and not only because Alice had to go to work. Rosa had her own job to do and it was the only way she would get her money and keep Roy Slack and Carlos Cruz happy while she secretly put in motion the plan to shed the skin of The Slayer and begin her new life with Alice.

It was 8am and it occurred to her that she hadn’t yet checked her messages. It was something she usually did as soon as she woke up but this morning she’d been distracted. Plus, her phone was still in her bag and her bag was in the kitchen where she’d left it last night.