‘There is one thing,’ Porter ventured. ‘The incident that’s taken place at her flat; our guys have taken a number of samples, fingerprints and hair from a hairbrush, to run some DNA tests. It’d be really useful if we could work out which samples belong to Natasha. That way we can tell if anyone else has been inside her flat.’

He was being economical with the truth, but it served no one’s best interests for him to disclose the contents of the freezer just yet, at least not until they knew for sure.

Locke looked confused. ‘How can I help with that?’

‘As her brother, you’ll have a certain amount of DNA in common. If we can take a sample from you, we can match that against any that belongs to Natasha.’

‘Are you saying she’s in trouble? Could she be hurt?’

‘We really don’t know at this stage,’ said Porter. ‘But things like this will help us try to find her and work out what’s going on. If you’re OK to do that I’ll arrange for somebody to come either to your office or your house to do a cheek swab.’

‘Of course,’ said Locke, his voice softer now as his thoughts drifted away to where his big sister might be and what kind of trouble she might be in.

He promised to come down to the station for the swab, preferring the anonymity it would give him as opposed to officers turning up at his home or office. They all left together and shook hands outside before heading off in different directions. Porter looked over his shoulder as they walked towards their car, making sure Locke was definitely out of earshot.

‘Stop me if you think otherwise,’ he began, ‘but I think we’re both fairly confident the cheek swab will match up to the sample from the hand.’

‘I’d lay money on it,’ agreed Styles.

‘So the question, then, is whether Ms Barclay bled out once she parted company with her hand, or whether whatever led to that sent her into hiding somewhere. We’re fairly sure it didn’t happen at the flat, so it’s pointless checking old records at local A & Es just yet.’

Styles jumped in before Porter could continue. ‘Agreed. Realistically, without medical attention, we’re looking for a body rather than a scared woman in hiding. I say we find out more about the dad, and how he met his maker. If he had something to do with whatever happened to her, that could be what tipped him over the edge.’

Porter nodded in agreement. ‘I’d like to read his note if it’s on file anywhere. I’d also like to know where he got his hands on the gun he used to kill himself.’