The Chain(73)

“She’s not as old as she pretends to be and she’s not as smart as she thinks she is. She was bluffing with me when she was talking about philosophy,” Rachel continues. “That’s not her area of expertise.”

“What makes you think it is a woman?”

“I can’t put my finger on that. But I know I’m right. I was talking to a woman who was using a voice-distortion machine.”

Erik nods and writes something in his notebook.

“Were you contacted by burner phone and the Wickr app?” he asks.

“Yes.”

He smiles. “The Chain has protected its security very cleverly. The anonymous phone calls using burner phones, the anonymous Bitcoin accounts that last a few weeks and disappear, the anonymous encrypted Wickr app whose ID gets changed periodically. The hiring of proxies to do the dirty work. Very clever. Almost foolproof.”

“Almost?”

“Some of it is unassailable. In my opinion, it would be impossible to backtrack through all the links of The Chain to find its origins. This is, of course, because of the pseudorandom element in the selection of the victims. You had a free choice of target, as did I, and so on and so on all the way back. Attempting to trace that trail to its origin will not work. I know. I have tried.”

“So how do we find the people who run The Chain?” Pete asks.

Erik picks up his notebook and flips through it. “For all my research, actually, I have come up with very little in the way of solutions. I—”

“You’re not telling me this whole meeting was a waste of time?” Pete interrupts.

“No. Their methods are good but when you are dealing with human agents, mistakes can be made. No agent is perfect in his or her tradecraft. Or so I suspect.”

“What mistake has The Chain made?”

“Perhaps they have become a little complacent, a little lazy. We shall see. Tell me about your last interaction with them.”

Rachel opens her mouth to speak, but Pete puts a hand on her arm. “Don’t tell him anything else.”

“We have to trust one another,” Rachel says.

“No, Rach, we don’t,” Pete says.

He doesn’t catch his own mistake but Rachel does and Erik does. Erik takes the notebook and presumably writes down Rachel.

We’ve come this far, she thinks. “It was a month ago. The first week of November,” Rachel says.

“They called you?”

“Yes.”

“And used the Wickr app?”

“Yes. Why is that so important?”

“The Wickr and Bitcoin accounts are protected by the highest levels of encryption commercially available, which would take tens of thousands of hours of supercomputing time to break. And I am certain that, at least in the beginning, they changed their Wickr app ID periodically for extra security. And, of course, there may be various layers of redundancy and dummy accounts. But even so, I believe I have found a flaw in their method of communication.”

“What flaw?”

The waitress opens the door and pokes her head in. “Will you be wanting to order food?” she asks in a Scottish accent.

“No,” Erik says coldly.

When she’s closed the door, he begins putting on his coat. “She’s new,” he says. “I don’t like new. Come on.”





54



A bench on Boston Common. A cold wind whistling in from the harbor. They’re opposite the memorial to Robert Gould Shaw and the men of the Fifty-Fourth Regiment. Not many people around. Just a few joggers, college students, people pushing strollers.

Rachel watches him and waits. When Erik finally feels safe he continues: “The standard construction of pseudorandom encrypted functions is generally believed to be leakage-resistant, but I don’t think it is. And when you have sloppy tradecraft, you make it slightly easier for people like me.”

“I don’t understand,” Rachel says. She looks at Pete. He’s in the dark too and he has a software background.

“They reach out to us in two ways, and both ways, I believe, can be decrypted,” Erik goes on.

“How?”

“The burner phones aren’t as safe as everyone thinks they are, even if all the calls are made from brand-new burner phones housed inside a Faraday cage. The consensus is that calls made by such a method would be completely untraceable,” Erik says with a grin.

“But you’ve thought of a way to crack it, haven’t you?” Pete says.

Erik’s grin broadens.

“This has been my primary area of research for the past year.”

“What’s the trick?”

“It is theoretically possible to measure power levels and antenna patterns through software that can be installed on a smartphone. The phone can then analyze the incoming call in real time.”

“You’ve done this?” Pete asks, impressed.

“I have been tinkering with such a concept.”

“You can trace a call made on a burner phone?”

“No, but the cell phone’s base station—the closest wireless tower—could possibly be found,” Erik says cagily.

“You’ve done it! Haven’t you?” Pete insists.

“Tell us,” Rachel pleads.