She smiled as all these pieces locked together in her mind, like a puzzle board. The ASCII art posts were encoded output, of a fixed length, with the exception of the final characters that referenced the crossword puzzle answers. Those solutions couldn’t be matched to random output, meaning they had to be chosen, and that in turn meant they must be part of the encoding process. So, what if the original message and the two crossword answers were all entered into specialised software, using a fixed-length algorithm to output the final encrypted text…which was then posted to the internet, disguised as a piece of ASCII art. All the recipient had to do was copy and paste the ASCII text, remove any white space and line breaks, and feed it back through the software using the two crossword puzzle answers as the key. Hey, presto, and the original message would appear.
It had been hiding in plain sight all along. The whole thing, staring her right in the face. Bridge took some solace from the fact that even knowing all this, without identifying the encryption algorithm that had been used, she still couldn’t have been expected to decode the messages when she and Ten were first looking at them.
But she could have had a bloody good go, and judging by the notes on his hard drive, that’s exactly what Ten had done. Methodically working through all the newspapers, and all the fixed-length-output algorithms, no doubt producing mountains of garbled nonsense before he hit on the one that returned a message. A date, a time, followed by words, names…and, in one instance, a phone number.
Bridge called it, and heard the recorded message informing her the number was out of service. That didn’t surprise her. If Ten had stumbled upon some kind of criminal enterprise (and what else could it be, with this level of secrecy and subterfuge?) then the messengers would use disposable ‘burner’ phones, cheap Android models from China and Korea that criminals bought by the dozen, and used just once or twice before dumping them in the Thames. If they hadn’t before now, realising their code had been broken by some random guy in London would have driven them to destroy their current phones.
Along with Declan O’Riordan.
She scanned the fourteen other messages. Most were the regular meeting schedules, or the shorter format which she presumed came from a second messenger. Three older messages also contained phone numbers, but like the most recent one, they were no longer in use. And then there were two messages that broke from the usual jargon:
Feb 10 - Existential/Libor - ☺Project codename EXPHORIA - source embedded☺
Mar 2 - Ballot/Trafalgar - ☺First handoff - success - delivery soon☺
Exphoria. It meant nothing to Bridge, but the message itself said it was a project codename, and the remainder of those messages made the hairs on her arms stand up.
Source embedded. First handoff. Delivery soon.
23
“How the hell do you know about Exphoria?”
Giles was already annoyed at Bridge for calling him out of his Friday breakfast meeting. When she then opened the conversation by asking what ‘Exphoria’ referred to, his reaction made her wonder if maybe this wasn’t the best way to begin.
“Wait,” she said, “let me back up. Declan O’Riordan sent me a scheduled email in the event of his death, and it led me to this.” She placed the hard drive on his desk. “It’s a cloned copy of the hard drive from his laptop. Five don’t know about it…” Giles’ eyes threatened to outgrow his glasses. Maybe this wasn’t the best tack, either, but now Bridge was committed, and she walked him through everything. From the moment she received the email on her phone the night before, through obtaining the garage key, finding the hard drive in the glove compartment, searching through the files on the hard drive, figuring out the encryption method, and finding references to the ‘Exphoria’ project codename, embedded sources, and handoffs. Finally she said, “Whatever Exphoria is, I think there’s a mole.”
Giles wasn’t often lost for words, and when he was, it was normally because of someone in Whitehall — frustration at a SPAD, PPS, sometimes senior mandarins or even ministers. But not this time. His mouth opened and closed in silence, then he narrowed his eyes at her while taking a long, steady breath.
At the back of her mind, she’d known her actions last night were at best rash and unauthorised, and at worst simply illegal, but she had to get to the bottom of it all. The problem was that she didn’t have the faintest idea what ‘it’ was until she read the decoded messages, and somehow she didn’t think that would cut much slack with Giles. He had the look of a man about to do something necessary but unpleasant — like, say, sacking one of his best analysts.
Giles thought for another moment, then leaned over and jabbed a button on his desk phone.
“Hello, IT?”
“Giles Finlay, floor seven. I need a clean laptop, in my office, soonest.”
“Five minutes, sir.”
Giles turned back to Bridge. “When that machine arrives you’re going to show me every file, every message, every code on this drive. Then you’re going to recount every detail of your movements last night, including however the hell you convinced the police to let you snoop around the victim’s home, until we’re done.”
“And then?”
“Then I’m going to decide whether or not to throw you on Five’s mercy.”
Ten minutes later, Giles had softened a little. Bridge guessed his main problem with her actions was simply that she hadn’t told him; if she’d approached him first he might have told her to go ahead anyway, because then he would have felt in control. But he also could have completely shut her down, seeing as all she had to go on was a gut feeling and a frankly suspect email. She’d calculated it was better to ask forgiveness than permission
