Extinction

There’s one in Shenyang.”

Jim shook his head. “Supreme Harmony is taking over the Chinese government. The network already controls the Guoanbu, and it’s giving orders to the local police forces. They’ll be waiting for us in front of every U.S. consulate in the country, because that’s where the network expects us to go.”

“Maybe we should head for the border then. Mongolia is four hundred miles away. That’s a lot closer than Yunnan.”

“No, that border’s guarded too well. We’d have a better chance of making it across the border between Yunnan and Burma. It’s a smuggler’s paradise down there.”

“But you’re not planning to cross into Burma, are you? You want to go straight to Supreme Harmony’s headquarters, right?”

Jim stopped digging. “I’m scared, Kir,” he admitted. “It’s not just about Layla now. We don’t have much time.” He looked down into the darkness where Kirsten stood, bracing his legs. “Let’s say we cross the border and make it back to the States. What’s gonna happen then? We’ll hand over our evidence to the NSA and their experts will start analyzing it. After a few days they’ll pass the ball to the White House, and then their experts will have a go at it. And by that time, Supreme Harmony will control the People’s Republic. It’ll have an army of three million men under its command, and a hundred long-range missiles armed with nuclear warheads.”

Kirsten didn’t respond. Jim waited a few seconds, then resumed his shoveling. By now he’d carved out a hole the size of a desk drawer, penetrating almost three feet into the wall. He stretched his left arm into the hole, shining the sat phone screen inside, and spied a gap extending all the way to the other side of the earthen barrier. He’d done it. He’d broken through. Now he just had to widen the gap. “Hey, hey!” he shouted. “This is gonna work!”

He expected Kirsten to let out a whoop or at least make a joke, but she remained silent. Jim shrugged, then continued digging. He scraped at the edges of the hole, steadily widening it.

After five more minutes, Jim leaned into the gap to inspect his progress. It was nearly wide enough for them to wriggle through. Another minute of digging should do it, he thought. Then Kirsten broke her silence. “You’re making a mistake,” she said.

Jim pulled his head out of the hole. “What did you say?”

“You’re letting your fears about your daughter cloud your judgment. You can’t single-handedly attack a Chinese government facility. That’s insane. It’s suicide.”

He peered into the darkness where Kirsten stood, still bracing his legs. He wasn’t surprised by the content of her remark. She was right—his plan was impractical, maybe even insane. He was pursuing it only because he couldn’t see an alternative. But what did surprise him was the tone of her voice. It was thick with anguish.

“Kir, I…” He didn’t know what to say. “I can do this. I have a plan.”

“Really? Well, lay it out for me.”

Again he heard the anguish, unmistakable. Kirsten wasn’t worried about herself, he realized. She was worried about him. She was heartsick with worry. Until that moment Jim hadn’t realized how much she cared for him. He felt like an idiot for not seeing it before.

He took a deep breath. He had his own hidden feelings, but this wasn’t the time to talk about it. Instead, he said, “I’m coming down,” and descended from his perch on the earthen wall. He stood in front of Kirsten and held the sat phone between them so he could see her face in the glow from its screen. “Supreme Harmony has a weakness,” he said. “Arvin told me about it just before he died. You’ve heard the term ‘Trojan horse,’ right?”

“Of course. It’s a harmful piece of software hidden in a computer system.”

“Right, it’s usually software. People are tricked into loading the harmful program into their machines because it looks legitimate. Then the Trojan can delete their files or steal their data. But a Trojan can also be inserted into the hardware. If a hacker has access to a chip-design facility or a factory that makes computer equipment, he can slightly alter a few of the circuits imprinted in a microprocessor.”

“And what’s the advantage of doing that?”

“Well, you can usually detect a software Trojan if you run a diagnostic on your system. But there are billions of microscopic wires and transistors in a processor. If you rerouted the wiring in just a few places, the alteration would be virtually undetectable. The processor would function normally and the user wouldn’t suspect a thing until the Trojan was activated.”

Kirsten cocked her head. Her glasses reflected the white rectangle of the sat phone’s screen. “Yeah, I heard something about this,” she said. “Weren’t there rumors a few years ago that the Israelis slipped a compromised chip into Syria’s radar system?”

Jim nodded. “That’s right. The chip turned off the radar just before the Israeli Air Force flew a bombing raid against a Syrian nuclear plant. The way it works is that the hacker waits until the right moment, then sends a specific code to the system. The code trips the altered circuit in the computer chip and initiates a new set of instructions. It could order the computer to erase every file in its memory. Or it could simply shut down the system.”

Kirsten paused, thinking. She raised her right hand to her chin. “So did Arvin put a Trojan in the processors of his implants?”

Jim nodded again. “He said he hid a shutdown switch in the circuitry. And there’s a code for activating it, a shutdown code, but it’s a little unusual. The code is incorporated into an image. Arvin’s exact words were, ‘It will turn them to stone.’ He meant that if a Module saw this image, the code would shut down its retinal implants and break its connection to Supreme Harmony.”

“Wait a second. How could that happen?”

“When a Module views the image, his retinal implants convert it to a stream of data, millions of zeroes and ones. And Arvin designed the image so that the stream contains the shutdown code, a particular sequence of zeroes and ones buried somewhere within the data. When this sequence passes through the implant’s processor, it trips the altered circuit and disables the chip.”

Kirsten gave him a skeptical look, pursing her lips and lowering her eyebrows. “And did Arvin show you this image?”

“No, but I found it in his visual memories. It’s a picture of Medusa, from Greek mythology. Arvin liked the symbolism, I guess.” He held up the satellite phone. “I downloaded it into my phone, but I’m not going to show it to you. I’m afraid it might shut down your implants, too.”

She still looked skeptical. She didn’t say anything for a while, and the silence of the Fangshan tunnel settled over them. Jim didn’t like this silence. It was heavy, oppressive. It was, literally, the silence of the grave.

Finally, Kirsten let out a sigh. “Are you sure about this, Jim? It seems like a convoluted way to deliver the shutdown code. Wouldn’t it be easier to just transmit the code wirelessly to the network?”

“That wouldn’t work. Supreme Harmony probably has a heavy-duty firewall that would filter out any suspicious transmissions from outside the network. But Arvin’s shutdown code is designed to go under the firewall. It slips through the network’s defenses by pretending to be just another piece of visual information for the Modules to process and analyze.”

She shook her head. “I don’t know. Even if you’re right, I don’t see how this can help us. Let’s say the Medusa image can shut down the implants. Can you really use it to take down the network? Are you going to walk up to the Modules with that picture in your hand and say, ‘Hey, guys, take a look at this’?”

“No, that wouldn’t work either. According to Arvin’s memories, showing Medusa to one of the Modules will disable its implants before it can share the image with the rest of Supreme Harmony. To shut down the whole network, we have to disconnect every Module. So we need to deliver the shutdown code to all of them at once.”

“And how the hell are you gonna do that?”

Jim didn’t have an answer. He hadn’t thought that far ahead yet. He wanted to say something to convince Kirsten that he knew what he was doing, that they had at least a slim chance of defeating Supreme Harmony. But, instead, he just stood there, biting his lip, and the tunnel’s silence settled over them again.

And then, just as the silence was becoming unbearable, Jim heard something. It was a low, familiar buzzing, echoing down the tunnel from the direction of central Beijing.