by Damien Boyd
‘OK, so we think we know the last-sent-to address for this particular transaction.’
‘Think?’
‘There are some situations when this might not work.’
‘Do I need to know?’ asked Dixon, turning to Louise and raising his eyebrows.
‘Not really. Look, focus on the bitcoin address. It’s a random string of letters and numbers – usually thirty-four. The address is only used once for a particular transaction and they’re largely untraceable. What I can tell you though is that we can be reasonably sure the last-sent-to address for this bitcoin now sitting in Steiner’s wallet was multi-signature.’
‘How can you tell that?’
‘It starts with a “3”. It’s to do with the address protocol. You don’t need to know that either.’
‘That’s a relief.’
‘Anyway, put it to him and see what he says.’
‘I will.’
‘A multi-signature wallet means that at least two people, each with a separate private key – think of that as a long password – control the bitcoin.’
‘Two people.’ Dixon smiled.
‘I thought you’d like that,’ said Watson. Then he rang off.
‘He tried explaining it to me as well, Sir,’ said Louise, dropping her chewing gum in the bin.
Dixon was jabbing the lift button with his finger. He had managed to grab a quick sandwich in the canteen, while they waited for Scanlon’s solicitor to arrive. ‘We’re going to have to keep it simple and hope he doesn’t understand the technology either. It’ll be all about his reaction.’
At least they had the interview room with the table this time.
‘You’re still under caution, Philip. Do you understand?’
‘Yes.’
‘I’ve spent the morning with Stella’s son, Nathan.’
Scanlon was looking around the room – the floor, ceiling, anywhere but at Dixon.
‘You’ve taken his father, his mother and his sister. How do you feel about that?’
‘Sorry,’ replied Scanlon, his eyes coming to rest on the table in front of him.
‘Do you want me to tell you how he feels about it?’
‘No.’
‘There’s only one thing you can do for him now. One thing that might bring him some crumb of comfort. And that is to let him bury his mother.’
Dixon waited, watching Scanlon sitting motionless in front of him. The fidgeting had gone, and taken with it any hint of remorse, by the looks of things.
‘Where is she?’ he continued.
‘No comment.’
Git.
‘Moving on then. I wanted to ask you about your accomplice. According to Myles you were at head office in Bristol the day Amy was killed and the day after. Is that right?’
‘Yes. It’s called giving yourself an alibi. It was supposed to be anyway.’
‘Who searched her room then?’
Scanlon frowned. ‘I have no idea what you’re talking about.’
‘Yes, you do. The file of papers that Stella had – the photographs. You hunted high and low and didn’t find it, did you?’
‘No comment.’
‘We have a witness who saw Amy leaving her mother’s house in Yatton with it. So, let me ask you again, who searched Amy’s room in the accommodation block? It couldn’t have been you because you weren’t there.’
‘No comment.’
Scanlon was fidgeting again now, beads of sweat on his forehead glinting in the strip lights on the ceiling.
‘We know someone did because two of the ceiling tiles had been glued back in position the wrong way round. Easy to spot that sort of thing when you live with someone with OCD.’
‘I have no idea what you’re talking about.’
‘You have previously admitted sending Steiner one bitcoin. Is that right?’
‘Yes. He gave me a bitcoin address and I made the transfer.’
‘From your own bitcoin wallet?’
Scanlon was pulling at the skin on back of his hand, his brow furrowed. ‘Yes.’
‘Is that an online wallet or on your computer?’
‘I have both.’
‘Which did you make the payment from?’
‘My online wallet.’
‘And where had the bitcoin come from to make that payment?’
‘No comment.’
‘My guess is that it came from a tarmac company. The same one that you were going to give the contract to once you’d taken it away from Hardman Tarmacadam.’
‘No comment.’
‘That’s fine.’ Dixon curled his lip. ‘I can work that one out for myself easily enough. There are only four companies pre-approved to bid.’
Scanlon closed his eyes.
‘I’m more interested in the other signatory to your bitcoin wallet.’
Eyes wide open now, Scanlon stared at Dixon, his breathing shallow and speeding up.
‘We’ve got access to Steiner’s Bitfly wallet and we can see the last-sent-to address of the single bitcoin sitting in there.’
‘No, you can’t.’
‘It’s in the blockchain, Philip.’
Scanlon hesitated. ‘What about it?’
‘It starts with a “3”. It’s the address protocol, or so they tell me. Can’t pretend to understand it myself. Odd that there are no “sent from” addresses too, so we have to make do with a last-sent-to, and this bitcoin was last sent to you, wasn’t it?’
Scanlon leaned across and whispered in his solicitor’s ear. She nodded.
‘No comment,’ he said.
‘Last sent to you and your accomplice, A. N. Other. In your multi-signature online wallet starting with a “3”.’
‘No comment.’
‘How about letting me have the login details? There’s a twelve word passphrase and then a pin number. Then they text you a verification code. We’ve got your phones, so that’s a start.’ Dixon smiled.
‘You don’t stand a cat’s chance in hell of getting in there. Do you have any idea of the level of encryption?’ Scanlon smirked. ‘Twelve random words from a list of two thousand and forty-eight. In the right order. Dream on. And they’ll all still be there when I get out too, because you bastards can’t confiscate them.’
Dixon shook his head. ‘I’ve got more chance of cracking your twelve word passphrase, Philip, than you have of ever getting out of prison. And even if you do, bitcoin will probably be worth peanuts by then.’ He turned to Scanlon’s solicitor. ‘Perhaps it’s time you two had a conversation about sentencing. And don’t forget, your client will be charged with five murders: the three workmen on the platform, Stella and Amy.’
Scanlon was shaking, his fists clenched.
‘Is there anything else you’d like to say, Philip, before we wrap this up?’ asked Dixon.
‘Fuck you.’
Potter had been watching the interview on the monitor in the next room and was waiting for them in the corridor.
‘We might as well charge him,’ she said. ‘You’re not going to get any more out of him, are you?’
‘It’s unlikely,’ said Dixon.
‘So, what happens now?’
‘We do it the hard way. If we can crack the bitcoin wallet, then the other signatory will get a text message alerting him we’ve logged in. Track that text and we’re home and dry. Or, better still, be standing next to the bugger when his phone bleeps. Make a start, Lou, will you. I’ll be back later.’
‘Where are you going?’ snapped Potter.
Dixon looked at his watch. ‘The vet.’
‘How do I make a start?’ mumbled Louise, as the door slammed behind Dixon.
Chapter Twenty-Nine
Barking.
It had been a good sign, thought Dixon, as he carried Monty out to the Land Rover. No sign of Jane and Lucy either, although they had left a note:
Gone to parents. Back later. Let me know what Tabi says :) Jx
He parked in the car park behind the vet’s and carried Monty into the crowded waiti
ng room. It never ceased to amaze him how a dog of Monty’s size could squeeze under an ordinary chair, his face peering out from behind Dixon’s legs. He was shaking too; not even the sight and smell of the cats had distracted him.
‘Monty?’ Tabi smiled. ‘I’m not sure who looks more scared, you or him,’ she said, watching Dixon carry Monty into the consulting room and place him on the table.
‘I had a shotgun pointed at me a few days ago.’ Dixon hooked his fingers in Monty’s collar. ‘This is worse.’
‘Well, it needn’t be. I wanted to show you this.’ She handed him a sheet of paper and traced the line of the graph with her finger. ‘This is his blood urea levels, indicative of kidney function. That’s the main risk with antifreeze poisoning. See the levels go up eight hours after he ingested it, just outside the normal range there though, and then they start to come back down. That’s yesterday there. Well within the normal range and it’ll all be out of his system now.’
‘So, he’s going to be fine?’ mumbled Dixon.
‘He’s not going to be fine.’ Tabi grinned. ‘He is fine.’
A single tear landed on the piece of paper, smudging the end of the graph. ‘I . . . er . . . don’t know what . . .’
‘Then don’t say anything,’ interrupted Tabi. ‘He may be a bit wobbly for a while. Keep him on bland food and I’ve given Jane some metronidazole to support his digestion; half a tablet twice a day. All right?’
Dixon nodded, the teardrops landing on Monty this time. ‘What about . . . ? Can he . . . ?’ Eyes closed, deep breath. ‘Go for a walk?’
‘Yes, that’s fine. Not too far to begin with. He’s still recovering and it will have taken a lot out of him. I’d like to see him again in a week, just to see how he’s getting on.’
‘Thank you.’
‘It was Jane who saved his life. And Lucy. I just followed the veterinary manual. They did the rest.’
Dixon lifted Monty off the table and put him on the floor. ‘No more carrying you everywhere, you lazy little . . .’ His voice tailed off.
‘Remember, short walks for a few days. No tennis ball.’
His phone was buzzing in his pocket as he paid the bill, Monty pulling him towards the door.
‘Do you want an itemised receipt?’ asked the receptionist.
‘No, thanks,’ replied Dixon, fighting the urge to blink. Just one would send the tears cascading down his cheeks again.
‘And another appointment in a week’s time. D’you want to make it now?’
‘Better had.’
‘Morning or afternoon?’
‘Either.’
He tucked the appointment card in his pocket and opened the door, his arm nearly ripped from its socket by Monty making his escape. ‘And no needles this time,’ said Dixon, squatting down and rubbing him behind the ears. ‘We live to fight another day, old son.’
‘Well?’ asked Jane, when Dixon finally answered his phone. ‘How is he?’
‘He’s fine. Thanks to you.’
‘What did she say?’
‘Kidney function is normal. Short walks for a while. She wants to see him again in a week.’
‘So, that’s it?’
‘It is.’
‘Where are you going now?’
‘To the beach.’ Dixon smiled. ‘Where else?’
‘It’s a beach, but not as we know it,’ said Dixon, lifting Monty out of the back door of the Land Rover and clipping on his lead. He had parked at the end of the lane, tight to the hedge, the huge viaduct of the Second Severn Crossing towering over them.
The tide was in, lapping at the lichen covered rubble along the shoreline, two dog walkers in the distance upstream on the concrete path that followed the base of the sea wall; railings along the top and a tarmac road behind it.
Dixon followed the track down to the water’s edge underneath the bridge, eerily quiet, despite the traffic above, the only sound the water lapping at the concrete slipway. Above him the viaduct curved away into the distance, the bridge towers in the middle at least a mile away.
‘You can have a potter about,’ he said, a text message arriving just as he was unclipping Monty’s lead.
We’re on Berrow Beach. Where are you? Jx
Severn Beach. Sorry! Nx
He didn’t have to wait long for Jane’s reply.
Doh! :-(
He looked up at the green monorail track on the underside of the viaduct, imagining workmen on suspended platforms either side bolting it in place. Not difficult here, he thought, only fifty feet or so above the ground, but out there in the middle, several hundred feet above the raging River Severn? That must have been a different matter altogether.
The maintenance compound behind the sea wall was all that was left of the original construction site, probably. Vast once, it now covered an area the size of a couple of tennis courts, with two prefabricated units, a container and four vans behind high security fencing. Several stacks of traffic cones too.
Steel steps rose up to platforms either side of the monorail track, a yellow boxcar sitting in the station. It looked more a like a steel container with windows than a train carriage.
‘I bet there’s no buffet car either,’ muttered Dixon.
He followed Monty back up to the concrete track, heading upstream towards the old Severn Bridge, just visible in the distance. Oddly enough he could hear the traffic now and looked back to the viaduct, following several lorries as they crossed into Wales.
Somewhere near where Liam had parked that night in 1995 too. Poor sod. And he had been innocent all along.
A bunch of flowers was fixed to the railings with cable ties. Ages old, by the looks of things, the colour gone, the plastic shredded, most of the petals ripped away by the wind. He reached up and pulled out the card, wedged between the stems. Smudged by the rain, but he could still make out the message. Just.
Liam, still fighting, love you always, Stella xx
He swallowed hard, dropping the card into his pocket and turning into the wind. Still fighting?
You won, Stella.
A twelve word passphrase. He had pretended not to have heard Louise when he left Express Park, but she was right. How on earth do you make a start? ‘Aardvark’, perhaps? He wondered if that really was the first word in the dictionary.
In the right order too. He remembered Scanlon’s sneer. Twelve words from a list of two thousand and forty-eight. What list? It narrowed it down a bit, but . . .
Maybe he’d buy a lottery ticket on the way home? He had more chance of winning that. Although perhaps he had used up his slice of luck lately, he thought, watching Monty sniffing a piece of driftwood.
It was an unusual view of Steep Holm out in the Bristol Channel framed by the huge concrete pillars of the viaduct, so he slid his iPhone out of his pocket and took a photograph of the island, just visible through the haze. And a picture of Monty, which he sent to Jane.
A few more photographs under the viaduct, and some of the monorail. He checked the zoom on his camera. It was impossible to get a sense of the scale of the thing, even with his dog in the foreground.
He began scrolling through the photographs he had taken, deleting two that had come out blurred, and one more of the view towards Avonmouth – hardly picturesque.
That left eight, making a total of five hundred and twelve. He’d have to watch the memory on his phone.
Five hundred and twelve photographs. And most of them of Jane or Monty on a beach somewhere.
He sighed.
For fuck’s sake.
An hour later Dixon was running along the landing at Express Park with Monty trotting along behind him. He jerked open a filing cabinet and pulled out the report on Scanlon’s personal mobile phone.
‘Look at you!’
He spun round to see Louise leaning forward on her swivel chair, both hands rubbing Monty’s back.
‘You got on all right at the vet then?’ she asked.
‘He’s got the all-clear.’ Dixon was flicking thr
ough the photographs in the appendices. All of them had been printed off, so he tore them out of the report.
All twelve of them.
‘I spoke to Donald Watson about the twelve word passphrase,’ said Louise. ‘He says it’s a mnemonic seed phrase. You’re supposed to commit them to memory and the twelve words come from a . . . Hang on.’ She glanced down at her notebook. ‘BIP39 word list. It’s something to do with their conversion to binary code, but it’s seriously secure. He said you’ll never get in.’
‘Have you got the list?’
‘I can print it off.’
‘Thanks.’ Dixon headed for the stairs up to the old Incident Room on the second floor. ‘Where are Dave and Mark?’ he asked.
‘They nipped to the pub, I think.’
‘See if they’ll come back. Otherwise, it’s just you and me.’
Dixon had sellotaped the photographs in a row along the top of the large whiteboard on the wall and was sitting back on a workstation staring at them when Louise arrived at the top of the stairs with a copy of the list.
‘I was right,’ she said. ‘They were in the pub. They’ll be here in ten minutes.’
Dixon gestured to the photographs. ‘Each one of these is a reminder for Scanlon, a trigger, for the twelve word passphrase.’
‘Shit,’ muttered Louise. ‘They were on his phone.’
‘They were.’ Dixon reached down and clicked his fingers. Just once was all it took and Monty was sitting on the floor next to him. ‘The first thing we’ve got to do is check that this is the exact order they appeared in the photo album on the phone.’
‘Here’s the list,’ said Louise, handing Dixon a copy. Then she picked up a phone off a vacant workstation. ‘I’ll ring High Tech.’
‘What we don’t know is how cryptic he was being,’ he said, picking up a marker pen.
The first photograph was a simple picture of a large diamond, so he began flicking through the word list, writing the words ‘diamond’, ‘jewel’ and ‘panther’ underneath it.
‘Panther?’ asked Louise, frowning.
‘Surely you’ve seen The Pink Panther?’
‘Yeah, I have. It’s the one with Steve—’
‘Peter Sellers, Lou. It’s the one with Peter Sellers and the Pink Panther was a diamond. Anyway, you see if you can find any others you think might be it and I’ll move on to the next one. What did they say about the order?’