by Ian Hocking
‘Scotty,’ said Saskia, ‘the transmission is critical.’
Jago took her elbow and walked her away from Besson.
‘It’s important, maybe. Tell me why it’s critical.’
‘Proctor got this call moments before he walked into the West Lothian Centre with a bomb. Did he receive instructions from the person behind the bombing at that point? Or was it the last message to a loved one from a man about to lose his freedom? In either case, we must discover to whom he was talking. The second party might have been involved in his escape. Perhaps they are waiting for him, helping him.’
‘That “gut instinct” of yours?’
‘I suppose.’
Jago sighed. ‘Alright, hen.’
Saskia walked over to Besson, forced him to look her in the eye, and waited for his smile to answer hers. ‘You say it is unbreakable. Break it for me.’
Chapter Eighteen
Jago led Saskia through the foyer of the building, where a crowd of uniformed police had gathered. ‘They’re waiting for news about the service merger,’ said Jago, not stopping. Saskia smiled at a young officer. He winked back in the habit of her boyfriend-who-never-was, Simon. She looked at the linoleum floor and recalled her arrival at the FIB building in flip-flops, irritable with heat and curious about a case. Her secretary. The fridge. Beckmann’s button hole and its curious yellow flower. Now this cold. This mission.
Only variations on a fictional theme, Kommissarin Brandt. Whom do you hunt? Yourself or Proctor?
They passed through the vestibule, down some stone steps in a grassy slope, and stopped beneath a blue lantern. Smart men and women hurried by. Their heads were turned against the cold.
‘Here’ll do,’ Jago said.
‘Do you have a spare cigarette?’
‘I do. Could you not buy your own?’
‘No. It would shatter the illusion that I do not smoke.’
He knocked two examples into his hand. He gave one to her and produced his lighter.
The lighter.
The feeling that returned.
Her eyes closed.
Laughter. The flick of a playing card dealt on a table. The smoke transformed from wisps (lit cigarettes) to plumes (burning furniture, wood, an office, mannequins).
Someone saying, ‘Revenge should have no bounds.’
‘Saskia?’
She opened her eyes. Jago was holding her shoulders. A cigarette dangled from his lower lip. ‘Are you all right?’
‘I felt dizzy.’
‘Migraine?’
‘No. It is not that.’
‘Do you want something to eat?’
‘Eat? No, I’m fine. Light me.’
Jago seemed to think about that. Then he put his lighter to the cigarette. She glanced at it, but it was just a lighter again. Its mnemonic power was spent.
They watched people walk in and out of the building. She took a drag and held it.
‘You muttered something, Saskia. It sounded German: ootah.’
Ute.
‘A woman’s name,’ she found herself saying, knowing
‘Mean anything to you?’
She looked away. ‘No, Scotty.’
Jago nodded, his eyes narrow against the smoke. ‘But you know she’s a woman.’
~
Saskia sat at the head of the conference table. Opposite her, Jago leaned against a portable heater. Besson was tapping a pen on his teeth while Garland continued her research in the realm of her glasses.
‘OK,’ said Saskia. She pressed her cold feet against the floor, stilling them. ‘Let us hypothesise that Proctor did not intend to encrypt this transmission.’
‘Why that?’ asked Jago.
‘Tell me: who sent the transmission?’
‘Who? Proctor.’
‘Fine, Scotty. Why do you say that?’
‘Well—’
Besson pointed at Saskia with his pen.
‘You’re right. We grabbed the transmission on the basis of a surveillance tape from a camera outside the hotel of Proctor talking in the taxi. We don’t know who initiated the call. We know nothing. We just have a terabyte of scrambled crap that was received and transmitted by Proctor at that time.’
Jago looked at both of them. ‘What are you saying? Someone sent a message to Proctor?’
Saskia nodded. ‘My gut feeling, Scotty, is that Proctor would not have waited until he reached the West Lothian Centre—’
Jago groaned. ‘Besson, you can forget you heard that, too.’
‘Naturally.’
‘My point,’ continued Saskia, ‘is that he knew he would be under surveillance. Why would he encrypt a transmission and then allow people to see him making it? This would counteract the purpose of encryption: concealment.’
‘OK,’ said Jago. ‘I’ll go for that.’
‘So, we need to determine the names of any individuals, perhaps of a mathematical persuasion, who may have contacted David Proctor, an Oxford professor. Charlotte?’
‘Heard you,’ she said. ‘I’m on it.’
‘Paul,’ Saskia prompted, ‘you said that the one-time pad would be a large list of numbers.’
‘If we were talking about a text message it would be large. But we’re talking about a broadband audio-video transmission: a good quality visual image changing up to thirty times a second, plus two sound tracks.’
‘So the list of numbers for the pad would be very large. What if Proctor used…a list of telephone numbers?’
Besson pouted. ‘Sure. That would be a start. But telephone directories are systematic and have a limited range of numbers. When you limit the range, you limit the complexity, and you make it easier for a cracker. Plus, you’d need to widen the net of the telephone directory to a country, perhaps, in order to make the ciphertext the same size as the plaintext.’
‘Listen, people,’ Jago said, ‘we’re not talking about Nazi High Command sending out the order to fire torpedoes. He’s just one man.’
‘Is he?’ asked Saskia. ‘He was aided in his escape. Charlotte, what do you have on his family?’
‘One minute.’ The red-haired woman’s eyes roamed. ‘His parents are dead. He has an uncle living in Israel who turned up after an invasive search. I’d bet that they don’t know of each other’s existence. His daughter, Jennifer, left for America four years ago, aged sixteen. She attended a school for gifted children in New York and graduated, aged eighteen, with a double degree in mathematics and physics. Her current whereabouts are unknown.’
Jago snorted. ‘What do you mean, unknown? I couldn’t wipe my arse without a computer somewhere going “beep”.’
‘Exactly that, Detective Inspector. She has no bank account, no passport, no social security number, and no insurance of any kind. She has no bonds or shares. Her records would lead anyone to the conclusion that she died aged eighteen. But there is no death registration.’
Saskia nodded. It made perfect sense. ‘Think of Proctor’s life from 2001 to 2003. Are there any similarities with his daughter’s situation?’
Charlotte frowned, blinked, and nodded. ‘Yes. During that period Proctor’s comings-and-goings are blank, just like his daughter.’
‘In that time,’ said Saskia. ‘Proctor was an employee of a high security research facility known as the West Lothian Centre.’
Jago sighed pointedly. ‘Alright. You think we have a daughter who entered her father’s profession. And perhaps called her father right before he went into the hotel and down into the lab. Did she come back to England to aid his escape?’
‘If this alley is blind,’ said Saskia, ‘then we can retrace our footsteps. Proctor is moving. I am certain that this transmission is critical to his movements, and we need to act quickly.’
Jago shrugged. ‘Fair enough.’
‘The identity of the caller is the key. Can we see the surveillance footage of Proctor’s arrival at the West Lothian Centre?’
‘It’s classified,’ said Besson sadly.
S
askia lifted the phone handset and dialled a number whose digits she had not thought of until this moment, and waited, a wink for Jago, as a phone rang in Berlin.
~
The headache burst not long after she hung up on Beckmann. She waved away the concerned hand—Jago or Besson, she could not tell through her narrowed eyes—and groped for the glass door. She walked the corridor blind. The metronomic click-clack of her shoes spoke to deep memories, and her nausea grew.
The toilet was arctic. She opened the tap and let her cupped hands full of water, seething but chill, and she dropped her face into the swirls.
Do I get migraines? she asked her chip. Is this normal?
It was silent.
She pressed her temples. If she pushed hard enough, could she override this pain with another?
Whom do you ask? said that unfamiliar voice in her head. Me or you?
Saskia looked at her reflection. ‘Who said that?’
Whom do you hunt? Proctor or yourself?
Saskia followed the shape of her mouth. ‘This. Is. Me. Talking.’
Confused?
‘Who are you?’
The hawk.
‘The hawk that returned?’
Spin, measure, snip.
She closed her eyes. Her imagination opened on a snowy archipelago. Each memory formed an island bridge: the Zippo lighter in Jago’s hand; the statue of Prometheus at the West Lothian Centre; the name Ute.
And smoke.
At first, it would be mistaken for smoke from a cigarette. Then its deep, toxic wave would overwhelm. Plastic. Coughing. Yes: panic.
A building on fire.
‘Is this the key to the cipher?’ she asked the archipelago. ‘Is this my key?’
Whom do you ask?
‘Who said that? What are you?’
Ute.
‘What about her? What about her?’ Saskia grasped desperately at the ghost of the memory.
~
‘Kommissarin?’
Saskia gave a start. The archipelago slipped aside like an inner eyelid. She blinked. She was still in the toilet cubicle, in the basement of the police station, and Charlotte Garland held her arm. She was not in…
‘Saskia?’
…in Cologne.
Chapter Nineteen
Besson opened his clamshell computer. The heat of his fingertips summoned a keyboard, red-glowing, as Jago, Saskia and Garland watched a projection on the wall. One pane showed a taxi against the frontage of the Park View Hotel. The other was crowded with a set of image processing tools.
‘I’ll say this for you,’ murmured Jago. ‘You’re well connected.’
‘I am,’ Saskia replied. ‘Paul, go.’
They watched the video from beginning to end. The story was simple: a car drove in from left of frame and stopped; Proctor opened the door, hesitated, then closed it. The windows remained opaque with reflected sky. Five minutes later, he opened the door a second time and walked out of the frame. The taxi drove away. For a period during those five minutes, he had made the transmission.
Saskia asked, ‘Ideas?’
‘The door,’ said Jago. ‘Why did he open it twice?’
‘Yes. He is the only person in the car. What model of car is that? Does it have an advanced computer?’
Besson shook his head. ‘That’s a Merc with a hands-off driving module. The computer is thick.’
Saskia approached the projection. ‘McWhirter said that Proctor used an industrial prototype to detonate the bomb. Perhaps his computer handled the communication too. Picture it: Proctor arrives, he opens the door, then the computer calls him back in. He closes it again and receives the transmission.’
Jago grunted. ‘Maybe the computer announced the caller.’
Saskia clicked her fingers. ‘One day, you will make a fine Kommissar, Deputy.’
‘Gee, thanks.’
‘Paul, can we see a plot of the sound at that point?’
Besson nodded. On the projection, Proctor reversed towards the car and opened the door. Besson wound it back still further. The door closed. He kept cuing. Thirty seconds later—for Proctor, five minutes earlier—the door opened again. ‘Alright,’ Besson said, ‘here’s a visual of the sound.’ The image was replaced by two graphs, each with a tiny peak halfway along. ‘I’ll play it. Quiet.’
As it played, Saskia heard a component deep inside the sound. It might have been a footfall, a snapping branch or a voice.
‘Anyone?’ she asked.
‘Hold on, I can enhance it.’
They waited for Besson to select a smudge in the spectrogram.
‘This is it. Quiet again, please.’
A voice, swept with wind, said, ‘Professor Proctor, it is your daughter.’
Saskia clapped Besson on the back and shared a nod with Garland.
‘N’bad,’ said Jago.
~
While Jago spoke to his boss about arranging an interview with Jennifer Proctor, Saskia donned her glasses and monitored the virtual workspaces of Besson and Garland, who were engaged in a review of communications between David and Jennifer Proctor. Pictures and text fluttered into the foreground and disintegrated, or joined to represent relationships suggested by Nexus, the semantic parser used by the UK Police Service.
‘Interesting,’ said Garland. ‘David Proctor is flagged for surveillance. Turns out this isn’t the first time he’s blown something up at the West Lothian Centre.’
‘How does that help us?’
‘Here,’ said Besson. In Saskia’s glasses, a data tile rushed towards her. She stopped it with a thought. It was a scan of a paper document, headed ‘GCHQ’. ‘Proctor has been flagged since 2003. Some analysis has already been carried out on his correspondence.’
‘Can we use that to our advantage?’
‘It should speed up the process. Hey, Charlotte, is that video of our man?’
‘Yeah. A robotics conference in Amsterdam in ’21. Looks like Proctor was the keynote. Nothing doing, though.’
Saskia tuned out. Beyond the graphical interface—which she could slide away on command—was a world where she had committed murder. There would be data for that too. Photographs. Video footage. Court documents. Witnesses.
In Cologne.
And yet she could not investigate a datum of it. The previous morning, when she had stood with the revolver in grisly salute, Beckmann had marked her limits. Any attempt to investigate herself would not be tolerated.
Forget it, Brandt.
‘Wow,’ said Garland, ‘look at this.’
It was an email. Garland highlighted some text in the centre and tossed it towards Saskia.
b2kool 2 use an encrypted transmission, dad
‘What did her father say to that?’ asked Saskia.
‘The reply is missing.’
‘Shame.’
‘Kommissarin,’ said Besson. ‘Read these.’
In the latest transmissions, Proctor seldom wrote more than two lines. They were invariably apologetic: ‘Sorry I can’t write any more right now,’ ‘CU Gotta go,’ ‘Write more soon, I prooomise!’, and so on, but the follow-ups were never sent. Jennifer’s e-mails shortened. She made jokes about her father’s tardiness, jokes that became sardonic and accusatory. At the same time, Proctor’s replies became defensive, hurt and confused. The messages described a dying relationship. Saskia could not suppress her sadness.
The e-mails dried up. There was no code.
‘Okay,’ Saskia said. ‘Tune out for a moment.’ She removed her glasses and watched their faces. ‘Charlotte, the e-mail about the cipher. When was that sent?’
‘Back in ’21,’ said Garland.
‘The cipher would have to be complicated,’ Besson said.
Saskia looked at him. ‘You said something earlier about using one-time pads to teach students the basics of cryptanalysis. Maybe she completed it as part of a school project. What was the name of her school? The one in New York?’
‘Wayne’s College,’ said Garland
.
‘Find their electronic documents archive. Search for projects by Jennifer Proctor.’
Garland smiled. All three replaced their glasses. Garland tore through the data and Besson and Saskia followed in her slipstream. A list of projects appeared. One was titled: ‘An algorithm for one-time pad encryption using the Homo sapien haploid genome, by Jennifer B. Proctor’.
Quite unexpectedly, Saskia thought of Simon.
‘Bingo,’ she said.
‘Proctor’s DNA was sequenced in 2017,’ said Garland, ‘as part of a research project at the Institute for Stem Cell Research, University of Edinburgh. The sequence was on a thumbdrive in his office when it was raided by MI5. There’s a copy bundled with the GCHQ data. Besson?’
‘Got it. Looks like about 750 megabytes. Not a strong OTP after all, though it might have taken us years to crack using a brute force method. What does Jennifer’s project say about a hash function? I’ll start with no hash and a simple XOR of the data against the DNA sequence.’ Besson smiled. ‘It worked. We have it.’
~
Detective Superintendent Shand took a box of paperwork from a chair and dropped it into his wastebasket. Saskia settled into the empty seat. Politely, she smiled about the narrow, high-ceilinged office. Jago sat on the windowsill.
‘Always good to meet our continental counterparts,’ said the DSI. He had a grey goatee beard and a lopsided, friendly expression. ‘Treating you well?’
‘Saskia made the breakthrough in the Proctor case,’ Jago said.
‘Team effort,’ she replied. ‘We now have a full transcript of the conversation that took place in the car between Proctor and his daughter.’
Jago gave him a sheaf of loose A4 paper, creased lengthways. The DSI glanced through. ‘Nothing jumps out. You two have had time to think about it. Talk to me.’
‘I have a hunch,’ said Saskia. ‘I think that Proctor has left the country, perhaps via an airport.’
‘Why?’
‘He has received a threat to his life. His daughter says, “Watch your back. Something may happen.” This warning comes true, does it not?’
The DSI arched an eyebrow. ‘I thought that the “something” was a result of Proctor’s own actions.’
