“How well was it hidden?” asks Claudia.
“Billy?”
“Executable .bat file. Not completely entry-level.”
“My instinct about this guy,” Eve says, “is that he would consider himself clever enough to create an uncrackable password. He’ll have informed himself about things like information entropy…”
“Like what?” asks Zbig.
Niko rubs his eyes. “Password strength is measured in entropy bits, which represent the base-2 logarithm of the number of guesses it would take to break it.”
Zbig stares. “Sorry… what?”
“You don’t need to know all that,” says Claudia. “What Eve means is that our target is smart enough to know that the password will have to be obscure, it will have to be long, and it will have to incorporate different types of characters.”
“He’s arrogant,” says Eve. “It won’t be something random. The password will mean something to him. Something he thinks no one will ever guess. And I’d put money on the fact that there’s a clue in plain sight in his office, which is why Billy photographed everything on his desk, on the walls, and in the bookcase. We’ve just got to out-think him.”
Lance reappears, smelling of cigarettes, and Billy spreads out the A4 prints. There’s a shot of the desktop, showing Cradle’s computer, landline phone, anglepoise lamp, DAB radio and binoculars, as well as miniature busts of Mao Tse Tung and Lenin.
“Communist kitsch,” murmurs Niko. “Dickhead.”
The shots of the books show copies of Shakespeare’s Hamlet, Machiavelli’s The Prince and Donald Trump’s Great Again, political thrillers by John le Carré and Charles Cumming, memoirs by David Petraeus and Geri Halliwell, and two shelves of Intelligence-related titles.
Other photographs are of pictures on the study wall. The students in the university dining hall, Cradle shaking hands with the U.S. four-star general, the salmon-fishing shots, and the family holiday snaps.
“Remember,” Eve says, as she refills the kettle for another round of tea. “The word or phrase we’re looking for could have as many as thirty characters. Think of quotes. Ex- public-school types like Cradle love quotes; they’re a way of showing off how well read they are.”
An hour passes, punctuated by speculative bursts of talk, flurries of key strokes, and the growl of night-traffic on the Tottenham Court Road. Lance goes outside for another roll-up. A second hour passes. Hangovers begin to bite, faces take on a defeated aspect, and Zbig mutters in Polish.
“What did he say?” Eve asks Niko.
“He said that this is about as much fun as fucking a hedgehog.”
“Right, well, let’s take a break and see where we are.” She stands up and looks at the others. “Can I have your best guesses so far? We’ve got three attempts at this password before the system locks down, so before we try one we need to be really sure we’re in with a chance. Niko, do you want to go first?”
“OK. My best shot is something based on ‘Methinks it is like a weasel.’”
“Don’t get it,” says Eve.
“It’s a quote,” says Niko. “From Hamlet. There’s a copy of Hamlet in the bookcase.”
“So?”
“The Weasel Program is also the name of a mathematical experiment by Richard Dawkins. It’s based on the theory that, given enough time, a monkey hitting random characters on a typewriter could produce the complete works of Shakespeare. Dawkins says that even if you just take the phrase ‘Methinks it is like a weasel,’ and a keyboard limited to twenty-six letters and a space bar, it would still take a high-speed computer program longer than the life of the universe to generate the correct phrase, given that there are…”
“Twenty-seven to the power of twenty-eight possible combinations,” says Billy.
“Exactly.”
“Would our subject know about this Weasel thing?” asks Claudia.
“No reason why not,” says Eve. “And Hamlet is definitely the odd one out in that bookcase. Anything else, Niko?”
He shakes his head.
“Scream If You Wanna Go Faster?” suggests Claudia.
“That’s not from Hamlet,” says Zbig.
“Funny guy. No, it’s Geri Halliwell’s second album. I bought it when I was sixteen. I used to sing ‘It’s Raining Men’ into my hairbrush in front of the bathroom mirror.”
“Zbig?”
“How about The Naïve and Sentimental Lover… It’s one of the le Carré titles.”
“That’s good,” says Eve. “I can see our man using that. Any other thoughts, anyone?”
“I don’t like any of them,” says Billy.
“Any particular reason?” asks Claudia, closing her eyes and bowing her head.
“They just sound wrong,” says Billy.
“You don’t think any of them are worth a try?” asks Eve. “In any form?”
Billy shrugs. “Not if we’ve only got three tries before we’re locked out, no. We’re not there yet.”
“Lance?”
“If Billy says we’re not there yet, then we keep looking.”
“I’m sorry, everyone,” Eve mutters. “You must be exhausted.”
Claudia and Zbig look at each other, but neither speaks.
“Those printouts,” says Niko. “Shuffle them, then lay them all out again.”
Eve does so, and they stare at the A4 pages in silence. A minute passes, then another. Then, at the same moment, as if by telepathy, both Claudia and Niko place an index finger on the same sheet. It’s a photograph of Penny Cradle with the children, Daniel and Bella, in a vast square in front of an ancient, pillared building. Penny is smiling a little fixedly, and the children are occupied with ice creams. In the bottom right-hand corner of the photograph someone, presumably Cradle, has written “Stars!”
“What?” says Eve.
“Not what. Why?” Claudia replies, and Niko smiles.
“I’m not with you,” says Eve.
“Why this photo?” says Niko. “All the others are show-off shots, chosen to prove how important and successful this guy is. The high-profile acquaintances, the expensive long-haul holidays, the salmon fishing, and the rest of it. But this one’s just… I don’t know. The wife looks stressed, the kids look bored. Why does he call them stars? Why’s the photo there?”
They all lean closer. “Wait a minute,” says Zbig, his voice low. “Wait a fucking minute…”
“Tell us,” says Eve.
“That square’s in Rome, and the building behind them is the Pantheon. You can’t see it, but there’s a carved inscription on the front of it. Marcus Agrippa, Lucii filius, consul tertium fecit. Marcus Agrippa, son of Lucius, built this when consul for the third time.”
“So?”
“Wait till you see how it’s actually written. Billy, can you Google ‘Pantheon inscription,’ and print us an image?”
Eve snatches the single sheet as it issues from the laser printer. Beneath the pediment of the building, the inscription is clearly legible:
“Now that looks like a password,” says Claudia.
Eve nods. “Billy?”
“I like it. Nice high entropy.”
“So let’s try it.”
A flurry of keystrokes.
Access denied.
“Try just the letters without the spaces,” Eve suggests.
Billy does so, and this time Niko turns away, and Zbig swears in Polish.
Eve stares at the screen with exhausted eyes. She looks back at the A4 print, at the sunlit square and the family group, and something falls quietly and precisely into place. “Billy, for the first attempt, you used upper-case letters and full stops, yes?”