Robin knows when he’s beaten. ‘Yes, guv.’

‘Now piss off.’

Robin doesn’t wait to be told twice. He walks quickly back to his desk, then picks up the phone, leaving a message for Greg to hurry up with the forensic checks on the car and the porn.

The complaint from Amy Miller still burns, but it confirms one thing to him – she’s nervous. He must be on the right track. Something happened that day at the Premier Inn. And it wasn’t a nasty accident with a belt.

He thinks about the data they have. The telematics from the car, geotagging on the phone. Maybe if they can compare the two, find some points that correspond – places both his car and his phone went so it would definitely be Jonathan Miller – it would lead them somewhere new.

He picks up the phone and calls Greg again.

‘For fuck’s sake, I got your message, Butler. I can’t make them go any faster.’

‘No, it’s not that. Listen, if I send you two sets of Excel data, can you run one of your whizzy formulas? See if any of the GPS coordinates match?’

‘Yeah, run a VLOOKUP, simple. As long as it’s an identical sequence of information.’

‘Can you do that for me, if I send you the spreadsheets?’

‘Or maybe an Index Match…’

‘Can you do it?’

‘Yeah, sure.’

‘Now?’

A sigh from Greg. ‘You owe me, you dick. A proper introduction to the lovely Freya West, if nothing else.’

‘Deal.’

Robin quickly emails them across, then sits back in his chair to wait. He taps his biro on the desk for a moment, then gets up and carries his mug to the kitchen to make a coffee. When he gets back, the email’s waiting for him.

He opens it, his hand reaching for the mouse even before he’s sat down.

Greg’s merged the two spreadsheets into one. Hundreds of lines of data. GPS coordinates in columns, some highlighted in yellow.

‘You genius, Greg,’ Robin mutters as he opens Google Maps and starts typing them in.

It’s slow work, and dull. Every location identified has to be checked against the list of known addresses for the people in Jonathan’s life. His house, Kal’s house, Waitrose, his office. Where’s his DC when you need her to do the shit work? he thinks.

And where is West, anyway? Surely she should be done on her special assignment soon. How long does shitty admin work take? When he asked her about it, she was evasive; there was definitely something she wasn’t telling him. He’s not worked with Freya long, but from knowing her around the office her default position is articulating whatever’s on her mind. There is no filter between her brain and her mouth. So if she is quiet, then…