"I see," said Weston.
"We were wondering if you could help us identify who bought the phone," said Cullen.
"Do you have a serial number?"
Cullen handed him one of the prints. "This is from the supplier. Your central stock system said it came here."
Weston logged on to the PC on his desk. He swivelled the monitor around to let Cullen and Caldwell watch as he navigated through a sophisticated stock control system. He pointed on the screen. "There's the delivery. I'll see if I can trace the unit through to a transaction. The system's updated hourly, so we know exactly which units are on the shelf at any one time." He tapped away. "There. Arrived on the twenty-third, four twenty-three pm and out on the shelves the following morning, eight sixteen am."
Cullen checked the printout. "Good. This phone was activated on the twenty-fifth. Just after two pm. We know it was sold that day between eight sixteen and then." He looked at the big year planner on the wall and tried to think. "Is there any way you can check when that particular phone was sold?"
Weston nodded. "I can have a look at the transactions database for the barcode for those units." He pulled up another system, typed through a few screens. "Here you go. Found one. Sold at eleven thirty-two am."
Cullen scribbled the reference numbers down from the screen. "Any credit card or Clubcard information?"
Weston's finger traced along the screen. "Sorry, no. Paid by cash."
"Bollocks." Cullen clicked his pen a couple of times. He'd had high hopes for this.
"We've got the time and till, though," said Caldwell. "You can surely cross-reference that to the CCTV cameras."
Weston nodded. "Don't see why not."
"Don't you overwrite the recordings?" said Caldwell.
"Not for the last ten years or so," said Weston. "It's all DVDs and hard drives these days."
"Can you get us the footage?" said Cullen.
Weston beamed his white smile. "Sure thing."
*
*
*
An hour later, Cullen and Caldwell were back in the Leith Walk station car park, heading to the stairwell. Caldwell carried a Tesco
Bag for Life
filled with printouts of the transaction and stock systems and a DVD with the CCTV footage from all store cameras covering an hour either side of the transaction.
"The amount of information they keep is frightening," she said. "From a serial number, he managed to take it through to a transaction to all that CCTV footage. I shop there every other week - how many times have I been caught on their system?"
"Doesn't bear thinking about, does it?" said Cullen.
As they started up the stairs, Cullen's mobile rang. Charlie Kidd.
"Cullen, you're a hard guy to get a hold of."
"What is it?"
"You're not going to believe this," said Kidd. "I've found Martin Webb."
"Show me." Cullen was out of breath from running up the stairs.
Kidd wiggled his finger at the screen. "Look at this." He fiddled around in his browsing history, clicked on a link and a page popped up. "There." He pressed the screen so hard it discoloured, as if bruised.
Cullen squinted at the image. "What is it?" His mouth was dry. Then it hit him. The image was Martin Webb, the picture on his Schoolbook profile. "Where did you find this?"
"That search I told you about," said Kidd, "it came back pretty quick." He pointed his finger at the screen again. "That's your boy there."
Cullen's eyes darted around the screen. "What is this site?"
"Digby Models dot com," said Kidd.
"Martin Webb's a model?" said Cullen.
Kidd laughed. "Kind of."
Cullen was always frustrated with that sort of response from people. "Either he is or he isn't."
"That's just it," said Kidd. "I think he both is and isn't."
"Explain."
"Fine," said Kidd. "Don't interrupt, okay?" He paused to compose himself. "This is a photographic model site, right? This page is in their stock library, so it's just full of photos people can pay for and use in design or whatever, like adverts. Martin Webb has nicked a photo off this site, cropped it and pretended it was him." He pointed at the screen. "Here, watch this."
He pressed a few keys to open Photoshop, a program Cullen was vaguely familiar with from a brief flirtation with photography. Kidd pasted the image from the website into the application. There was a logo at the left hand side, obscuring part of the image, which he cropped out. He double-clicked, and created an almost exact replica of the image on Schoolbook.
"Jesus," said Cullen. "So how does this work? How did you find it?"
Kidd shrugged. "No idea. I just press the buttons."
Cullen laughed.
"Seriously, though," said Kidd, "I think it's something to do with just a string-matching search. An image is just a series of ones and zeroes in a set format. It's a case of matching your ones and zeroes with any other in that format. Get enough groupings of matches and you've got something." He grinned. "It just matches chunks of data. Pretty smart, eh?"
"This is good," said Cullen.
Kidd held up a sheet of paper. "Here you go. Something else for Bain's file."
"Cheers."
Cullen raced off towards the Incident Room and found Bain and Miller at their desks, Bain looking as pissed off as usual and Miller on the defensive.
"Ah, Sundance, there you are," said Bain. "Nice of you to pitch up."
The Tesco bag was on Cullen's desk. He held it up. "Got something for you."
"I hope it's custard creams," said Bain.
Cullen ignored him and took the DVD out. "It's CCTV footage from Tesco. We might be able to see who bought that mobile phone."
Bain looked disinterested. "Great."
"Try to sound a little bit impressed," said Cullen.
Bain grunted. "Have you watched it?"
"A bit." Cullen ran his hand through his hair.
"And?"
"Inconclusive at best," said Cullen.
Bain snarled a smile. "And I'm supposed to be
impressed
?"
Cullen ignored him. "Charlie Kidd's found something. The image on Martin Webb's profile came from a photographic model site on the internet."
Bain frowned. "Come again?"
Cullen handed him the sheet of paper Kidd had given him then explained the process in sufficiently simple language Bain would understand.
"So this profile's a total fabrication then?" said Bain. "Someone's created Martin Webb?"
"Looks that way," said Cullen.
"I'm thinking that someone is Rob Thomson," said Bain.
Cullen frowned. "I'd say we need a bit more evidence before we can definitively say it's him."
Bain turned round to Miller and tossed the DVD at him. "Right, Monkey Boy, I want you to look through this CCTV, see if it shows Rob Thomson buying Martin Webb's phone."
"We've not got proof it's Martin Webb's mobile," said Cullen. "We only know it was used to call Caroline just before she disappeared."
"That's a matter for the PF," said Bain. "We need to overload her with evidence." He rubbed his moustache. "We've got to prove Rob Thomson is Martin Webb, that's the only way to nail him."
"Did you get any more resource for me?" said Cullen.
"Holdsworth's going to get back to me by five with a name for you."
"I'll need more than one," said Cullen.
"Cullen, just quit moaning and get on with it." Bain walked off, muttering to himself.
"So, Scott, what do I do with this DVD then?" said Miller.
"Just watch it, Keith," said Cullen. "There's a guy buying a mobile phone, we want to know who it is."
"That it?" Miller's face lit up. "Happy days." He put the DVD in his laptop with a big smile on his face.
*
*
*
Cullen spent the next hour and a half calling through the friends list, soul-destroying work.
He could have done with another coffee, but he decided it was a carrot he needed to keep in front of his nose. There was the sound of a phone dropping to the desk. He looked over at Caldwell - her face was several shades paler than normal. "Are you okay?"
She looked up at him, eyes barely focusing. "Somebody just told me Rob Thomson made death threats to Caroline."
The new Edinburgh city morgue was situated in the basement of Leith Walk station. Cullen sat in the reception area, set aside for grieving relatives waiting to identify a body - sombre colours, well furnished, a metal box of tissues on the oak coffee table.
Debi Curtis' autopsy was just finishing according to Jimmy Deeley's assistant.
Cullen looked up on hearing Bain's voice - he seemed less than happy. He recognised the Procurator Fiscal as she marched off, thinking it unusual to see her at a post mortem, but then this was turning into an unusual case.
"Sundance." Bain didn't stop. Cullen had to hurry to catch up. "To what do I owe the pleasure?"
"I need to speak to you," said Cullen.
"Well, we're having a briefing," said Bain, "so you can wait."
"I need to speak to you
now
."
"Not now." Bain turned to face Cullen. "Whatever it is, Sundance, it can wait."
Cullen spun around and stopped in front of Bain, blocking his progress down the corridor. "It's about Rob Thomson. Evidence."
Bain huffed when he couldn't get past Cullen. "Go on," he said, with a great deal of reluctance.
"Caldwell's just found out Rob Thomson threatened to kill Caroline after their divorce."
Bain eyed him suspiciously. "Aye?"
"It was to do with the custody of their son, apparently," said Cullen. "It's common knowledge in Carnoustie."
"Fuckin' hell." Bain rubbed at his moustache, almost tugging at the hairs. "How tight is this?"
Cullen shrugged. "We'll get it backed up with a statement."
Bain checked his watch. "Right, it's time to bring him in."
Cullen went back upstairs to see Kidd.
"Whoever this Martin Webb guy is," said Cullen, "that's who's killed these two women."
Kidd scuttled his trackball out of frustration, sending it tumbling across his desk. "I know that."
"Well, how are you getting on?" said Cullen.
Kidd tossed his ponytail nervously, not speaking for what felt like an age. "I'm not getting on as well as I thought. I made a good breakthrough with that stuff last night, but that's the easy part. What I want to look at is the log files and that sort of thing."
"And why can't you?"
"It's like what we were talking about yesterday," said Kidd, "they haven't given us the header data for those tables."
"I thought they were giving us it," said Cullen.
"Aye well, so did I," said Kidd. "But they haven't."
"Who have you been dealing with?"
"That Duncan Wilson boy."
"Right, I'm calling him." Cullen flicked through his notebook and found a phone number.
"This is Duncan."
"Mr Wilson, this is DC Cullen. We met yesterday at your office."
Wilson sigh echoed down the line. "What is it this time? Why do you lot keep chasing me?"
"If you'd given us what you promised on that database extract," said Cullen, "then we wouldn't have to keep calling you up like this."
"Oh, okay," said Wilson. "This is Charlie Kidd's stuff, right?"
"It is." Cullen wondered what else it could be. "And if you want me to come back over there with uniformed officers to confiscate some of your servers, then you're going the right way about it."
"Do you want me to go to the press with this?" said Wilson. "I'm not sure how they'd view the police trying to strong arm a social network."
"And I'd be asking myself how they'd view someone using your social network to perpetrate two murders due to your lack of adequate security."
Wilson paused. "Okay, okay, fine. I'll need to run this by Gregor Aitchison first."
"I've already spoken to him," said Cullen, a barefaced lie. "Just send Mr Kidd what he needs and I won't have to pay you a visit."
"I'll be a few hours," said Wilson.
"Listen, if it's not here by five pm," said Cullen, "I'm turning up with some uniformed officers and crowbars."
"Okay, okay, okay."
"I don't want to hear anything about this again." Cullen ended the call.
"Think he'll play ball?" said Kidd.
Cullen gave a shrug. "I hope for his sake that he does."
Half an hour later Cullen sat in the Incident Room finishing a large beaker of strong coffee, a filter with two extra shots of espresso. He had only managed to get back to one person on the list so far and they'd not heard about the death threats. He checked his watch - five pm. It seemed to him their earlier luck had run out.
He looked through his list of Caroline's friends, ready to get back to calling people to check on the threats.
"Sundance." Bain had a wide grin on his face. He loomed over Miller, staring at a laptop screen a few desks over. "Come here. Have a look at this."
Cullen slowly wandered round. There was a video player open, black and white footage of the inside of the Hermiston Gait Tesco. "We watched this at the Tesco."
"Aye, but not on equipment like this." Bain tapped Miller on the shoulder.
Miller rewound the video until the display showed 11.24am then let it run. Cullen could just make out a large figure wearing a baseball cap walk across the screen towards the mobile phone area. He picked up a package from the GoMobile section of the display. Miller froze the frame.
Bain grabbed Cullen's shoulder, his face like a kid on Christmas morning. "It's him."
Cullen looked more closely at the image. "Who?"
Bain's nostrils flared. "Rob Thomson."
Cullen squinted at the display. "You think?"
Bain sighed. "Not you as well." He leaned into the screen, pointing at the figure and pressing so hard it deformed the display. "It fuckin'
is
him."
Cullen leaned forward even closer, tried to see it, but just couldn't. "I think you're reaching."
"Christ's sake." Bain drew a box around the figure with his finger. "Here, Miller, enhance that bit."