‘And you think that means something?’

‘We have to assume the whole point of that was to stop her escaping, to have control over her so once you shoot someone that need is gone. Why would you leave it?’

‘Why not?’

‘Because it tells us a story. It tells us that this wasn’t some burglary that escalated, it tells us that this was something a lot more serious. That helps us. Why would you do that?’

‘Because they wanted us to know?’ DS Rose said and plunged them both into silence. It was Sandra who spoke next.

‘I’m not one for getting hopes up but it does give us a forensic opportunity. Metal chains and clasps are good for traces, no matter how careful you are, lots of moving, pinchy bits. I’ve got lucky before.’

Joel took in the scene again. ‘I know that. I think the killer might know that too. If it were me, I’d have her shackle herself. If I’m the one with the gun, I’m the one with all the power, why risk doing it?’

‘It’s been brought here though. This isn’t something they’ve found lying around in the flat,’ Sandra retorted.

‘Which means it was premeditated. All of it. We know the occupant here is an informant, but nothing about what information she was giving, who she was talking about, what sort of offences even.’ Joel turned towards his DS, but her only reply was to give her shoulders a slight lift, her eyes still pulled to where her friend was laid out in front of her.

‘Ah, back to things we know. Somewhere I’m a lot more comfortable.’ Sandra’s stern exterior seemed to relax, there might even have been a smile behind her mask, and it eased some of the tension in the room. ‘We know the occupant is dead too. She was found—’

‘She’s dead?’ Joel cut her off, the surprise in his voice unavoidable, and he suddenly wished he had had the time to read the whole CAD.

‘No one tells you anything, do they?’ Sandra replied.

‘It would appear not.’

‘She was found at the same time and is still in the living room. Toxicology will give you the facts on that one but in normal circumstances my opinion would be a clear overdose. She’s surrounded by paraphernalia, she’s a clear user, track marks – everything you would expect,’ Sandra said.

‘You knew this was a double murder?’ Joel spoke to his DS now.

‘I did.’

Joel was quick to turn back to Sandra. ‘So these aren’t normal circumstances.’

‘Far from it,’ Sandra replied.

‘We can’t rule out that our drug user killed Hannah and then killed herself,’ DS Rose said. ‘Maybe she called her here with that intention?’

‘Maybe,’ Sandra answered.

‘You don’t think so?’ Joel said and Sandra licked her lips before replying.