“Quantum entanglement,” Blackburn agreed, raising his forearm keyboard and giving another shot to hacking Yuri’s processor. “Every single satellite is essentially one half of a greater computer, communicating through one set of an entangled pair of photons up there in space, the other half down here on Earth. This link is instantaneous, it can’t be jammed, and it can’t be hacked. Now imagine a certain Russian trillionaire has a quantum transmitter inside a supercomputer in Antarctica and an entangled counterpart transmitter inside a person’s brain.”

Wyatt drew a sharp breath.

“Same principles apply. You’ve got a connection that can’t be jammed, disrupted, or blocked. I figure Joseph Vengerov chose Mr. Sysevich very carefully for his transmitter. He found a likable, charismatic child of one of his employees—someone he had easy access to. He targeted a bright, driven, and optimistic young boy who was likely to go places in life. Next thing he did was shell out big bucks so this kid could go to the best schools, get in top physical shape, and really develop into something exceptional. That gave him a chance to place this kid—and the eyes and ears of this kid—most anywhere he wanted him.”

Wyatt’s hand flew to her mouth.

“Then he decided to stick his walking Trojan horse in the Pentagonal Spire, the better to keep his window into the installation after I took it over. As an added bonus, since the kid now had a neural processor funded by the US taxpayer, old Joe could do more than spy—he could remotely program that kid’s behavior, too . . . dictate his actions, use him to disrupt operations in space, maybe even conduct surveillance on persons of interest, wouldn’t you say, Raines?”

Tom felt strange, numb. So many things, so many vague suspicions, so many feelings he ignored began to resolve themselves into a now terribly clear picture. Yuri hadn’t told Vengerov about him. Vengerov had directly seen and heard him through Yuri.

“I found the transmitter in his head my first week here. We found pretense after pretense to run new scans of Sysevich’s brain, hoping to find some point of vulnerability so I could cripple that transmitter. But there isn’t any way to disable it. It was installed in his head when he was so young, his neurons developed around it. It’s as much a part of his brain now as his brain stem, as his cerebellum. It’s a separate device from his neural processor, yet it can be used to control his processor. Taking either of those devices out would kill him. And I’ve got to hand it to old Joe: it was a spectacularly ruthless way of making sure no one would ever remove it. After all, only a monster would kill a kid to neutralize a security threat.”

He began rubbing his palm over his mouth. A note of dark anger stole into his voice.

“Now that you know the situation, Mr. Raines, Ms. Enslow, let’s make very certain you understand what you’ve done to your friend.” He pointed at Yuri. “He is a walking, talking backdoor into our system, one that I can’t close. I wasn’t able to force him out of the program, because he had a very powerful patron who wanted to make sure he stayed here. If we booted Sysevich out, General Marsh would’ve had a deluge of senators calling for him to be replaced. The kid wouldn’t even consider leaving himself, because a write-protected sector of his neural processor contained some preinstalled, operant-conditioning algorithms to compel him to stay here, no matter what.”

Wyatt’s eyes shot wide open.

Against his volition, Tom’s mind turned back to Yuri on the stairwell that day after everyone climbed the Spire. Yuri had outright told him the thought of leaving was like some terrible weight pressing in on his temples. Now Tom felt so angry at himself, because he hadn’t thought anything of it.

He knew that sensation, the sense like a vise was squeezing his skull. Dalton’s program used that exact sensation when it was controlling him. Tom knew it, he knew it, but he hadn’t even made the connection.

“So you see now why I installed that filtering program. It jumbled all Sysevich’s sensory data. He couldn’t transmit anything useful to the other end. By stripping my program away, you gave Obsidian Corp. full access not only to Sysevich but to our entire system and every neural processor within it. We’re lucky this wasn’t worse.”

Tom had this vague sense he needed to do something, but he couldn’t seem to make himself move.

“Now I think it’s been long enough,” Blackburn muttered, turning on Yuri. The daemon program snapped to alertness, jerking Yuri’s head up straight, his body shifting into a defensive stance. “I don’t care how sophisticated a computer interface might be, I want to deal with a human being. I’ve given ample time for a remote administrator to assume control over Sysevich’s actions. I assume I’m addressing a person now?”

Tom’s gaze swung over to Yuri, and he made out Yuri’s tiny nod.

“Good.” Blackburn folded his arms. “I suppose you’ve anticipated my next action?”

“You intend to neutralize this asset,” Yuri said tonelessly.

“No, no.” Blackburn shook his head. “That didn’t quite pan out the last time. Neutralizing him gave someone a chance to reactivate him. I’m taking a different approach. You all have dumped Sysevich in my lap and you’ve fought every effort I’ve made to toss him out of it, so from this day forward, I’m going to use him against Obsidian Corp. I’m thinking of showing his processor off to some of your disgruntled ex-employees, rounding up some expert witnesses. They’ll take one look at the data on his processor and they’ll be able to honestly testify before the Defense Committee that Obsidian Corp. was manipulating Sysevich’s processor right around the time the breaches occurred. Sysevich is going to be my proof Obsidian Corp. backstabbed us.”

Tom saw Yuri straighten, growing rigid. “That won’t be allowed.”

Blackburn’s eyes gleamed. “It’s not your choice. There’s enough hard data in his processor to incontrovertibly prove Obsidian Corp.’s involvement.” He let that sit there a long moment, then added, “Unless someone, somehow, removed his processor from the Pentagonal Spire. Unless Sysevich no longer was in my lap, because someone finally decided his time was up and nothing was going to be gained by forcing his presence here.”

Tom’s mind processed the implications of what Blackburn was saying. He felt a pang of remorse, realizing it: Blackburn was forcing Vengerov to withdraw Yuri from the Spire. Vengerov would probably agree. Tom’s head pulsed, his insides stinging with the unfairness of it. Yuri didn’t deserve any of this.

For his part, Yuri—or the person controlling him—remained perfectly still and silent, listening to Blackburn set the terms.

Blackburn seemed to grow impatient with the silence. “Well?” He spread his hands. “The choice is yours. Leave Sysevich here and give me a weapon, or take him out of here and get his processor away from me.”

Yuri’s empty-eyed gaze slid over them and settled on Blackburn’s. A slow smile curled his lips, and something about it made Tom’s skin crawl.

“Very well. The issue is conceded. His processor will no longer threaten the integrity of the Pentagonal Spire. This asset will be removed from your custody, Lieutenant Blackburn.”

And suddenly, Yuri seemed to catch his balance, almost like he’d been nodding off while sitting in class or something. He straightened up, his face cloudy, perplexed, but it was him. It was actually him.