Since Angie had walked out of their foster home in the Black Country as a teenager, Diane had spent years trying to track her down. It had been her reason for coming to Derbyshire in the first place. Yet when they had finally been reunited, the taste of success had been a sour one. Diane had found that her sister was no longer a person she could trust.

‘You must have realized that I got mixed up in some things that I didn’t mean to,’ said Angie on the phone that night.

‘Obviously. The drugs –’

‘I don’t mean the drugs. Well, not the drugs on their own. There’s a whole world that heroin gets you into. You’ve no idea, Diane.’

And Diane had to accept that she really didn’t have any idea. She’d never thought of herself as naïve. How could she be? But there were things about her sister that she didn’t understand. She supposed that she never had understood them, really. It was probably that mystery, the constant hint of wickedness and the unknown, that had led her to worship Angie as a teenager. Not just sisterly love, after all. She had been drawn to the scent of danger like a moth to a flame. And Angie had, too. In that way, they were the same.

For a moment, Diane wondered whether her sister was involved in some gigantic conspiracy against her. Had she been seething with jealousy and hatred all these years? Was she determined to bring Diane down, one way or another? If she was, she was doing a damned good job, and Diane felt helpless to fight her intentions.

‘I was recruited,’ said Angie. ‘First by the bad guys, then by the good guys. It’s not always easy to tell the difference, though. Funny, that.’

‘You’ve been working for the drugs squad?’ said Diane. ‘As an informant.’

She realized it had been a suspicion that she’d been suppressing. She could easily have believed anything of her sister, but not that. The evidence had been there, in front of her nose, but she’d refused to believe it, had never even tried to confront it.

‘SOCA,’ said Angie. ‘The Serious and Organized Crime Agency.’

‘I know who SOCA are.’

‘You were very slow, Di. Your nice Constable Cooper figured it out long ago.’

Diane gritted her teeth. She was realizing another truth that she ought to have accepted a long time ago. Not only was her sister someone she couldn’t trust; worse, Angie had become someone she no longer knew.

‘How did Ben Cooper come into it? I never understood that.’

‘Oh, don’t take it out on him,’ said Angie, sounding faintly less sardonic. ‘He was only trying to help. It’s what he does. You must have noticed.’

Fry was within a second of putting the phone down. But she knew that she couldn’t leave a question hanging. It would torment her for days.

‘Angie, what is it you want?’ she said.

‘I want you to come back, Diane.’