I'm still not convinced. Hawke is wrong-there's always a choice. And yet I can't say no to the general. I retrieve a memory from my files, something I told Adam a few days ago when we were arguing about Hawke: Forget about yourself for a minute and think of the big picture. We have a job to do. And Adam said he agreed with me, a hundred percent. He loved to argue, but in the end he always did the right thing. Grief pierces my circuits. I miss him so much.

"All right," I tell Hawke. "But I'm going to make a few changes to the assault plan. I have to talk with my team before we launch the Ravens."

"Just make it quick. You gotta get to the computer lab before dawn. Once the sun comes up, the Ravens won't be invisible anymore."

Hawke lifts his hand from my shoulder joint and returns to his men. At the same time, I stride toward DeShawn, who's pointing his camera at the dark fields of the missile base.

DeShawn turns his turret as I approach. His acoustic sensor must've picked up the sound of my footsteps. "What's the word?" he asks. "When do we go?"

"Very soon. But first I want you to share some software with me."

"Sure, what do you-"

"The program that lets you occupy two machines at the same time. I'm going to need it."

I'm the first Pioneer to take off. I launch the Raven myself, hurling the three-foot-long plane into the sky above the clearing. Then I transfer my data to the drone's control unit.

Except for the darkness, it's not so different from flying the Raven above Pioneer Base. I use the drone's infrared camera to view the terrain. In the clearing below I see the warm bodies of the soldiers and the cold torsos of the other Pioneers. To the northeast the fires are still raging in the city of Saratov, but when I point the drone's camera to the northwest-toward Tatishchevo-I see only fields and wooded hills.

Within five minutes all the Pioneers have transferred to their Ravens. We rev up our electric motors and spiral upward, gradually vanishing into the night sky. Once we reach an altitude of five thousand feet we level out and arrange the drones in a V-shaped formation, with my Raven in the lead. Then we head northwest at forty miles per hour, cruising toward the missile base. No one on the ground can see or hear us. On a radar screen we would look like a small flock of geese migrating over the Russian countryside.

Soon we fly over Tatishchevo's perimeter fence. I spot several T-90 tanks behind the fence, positioned at key points so they can monitor everything approaching the base. This is crunch time, the moment of truth. If Sigma detects us and figures out we're not geese, the T-90s will fire their anti-aircraft guns. The high-caliber bullets will tear us to bits.

But the tanks don't fire at us. They don't move an inch.

A couple of miles past the fence I see one of the missile silos. It's in an inconspicuous spot at the edge of a field. The silo's lid is a cold steel circle, about twenty-five feet across, embedded in the ground. Scanning the terrain, I see more silos to the north and west. Dozens of them are scattered across the landscape. As I fly over the steel circles I think of the nuclear missiles standing below them. It's an inferno hidden beneath the dark countryside, a holocaust just waiting to happen.

I'm scared. No doubt about it. I'm scared to death. I want to turn around and transfer right back to my Pioneer. The five-pound Raven seems so puny and defenseless compared with my eight-hundred-pound robot. As we soar toward Tatishchevo's headquarters I get the feeling I may never return to good old Pioneer 4. I think of Adam again, and also my mom and dad. I don't know where they are right now-the Army wouldn't tell us where they'd hidden our parents-but I'm praying they're not in a big city or on a military base. If we can't stop Sigma from launching its nukes, I hope Mom and Dad are as far as possible from the blast zones.

Fifteen minutes into our flight I see something disturbing. Below us is a stretch of scorched ground and demolished buildings. The area is pitted with impact craters and littered with debris. According to the maps stored in my files, this was the site of the barracks for the 60th Missile Division. More than a thousand Russian soldiers were sleeping in those barracks when Sigma took control of Tatishchevo's automated T-90s. It must've been a nightmare, all those tanks firing at the terrified troops. My infrared camera picks up the heat signatures of rodents scurrying in and out of the wrecked buildings. It's been three weeks since the massacre, but the rats are still feeding on the corpses.

The headquarters complex is just beyond the barracks. When I'm a mile away I turn off my Raven's electric motor. The propeller stops spinning and I drop about a hundred feet before settling into a glide path. Now I'm absolutely silent as I descend toward the computer lab. The other Ravens cut off their motors too and coast behind me, heading for the same target. We're following a prearranged assault plan because we don't want to use our radios now. Sigma might be able to detect the transmissions from our Ravens.

After another three minutes I'm circling the lab and the neighboring buildings at an altitude of a thousand feet. The other Ravens are gliding in slow circles above me. Pointing my camera at the ground, I view the same buildings I saw in the satellite photo. I also see the five T-90 tanks. They're in exactly the same positions they occupied in the photograph-one at the lab's front entrance, the other four at the building's corners. This bothers the heck out of me. It seems too convenient, too easy. What if Sigma's already inside all the tanks? If DeShawn could figure out how to occupy two machines at once, what's to stop the AI from doing the same?

Still circling, I glide down to five hundred feet. At the same time, I load DeShawn's program. I've modified the software to give myself a fallback option. The program will copy my files and transmit them to the T-90's control unit, but if Sigma's already there and I need to make a quick exit, the software will delete the copied data and allow me to pull back to the Raven. It's the equivalent of dipping a toe in the water to check its temperature. I'm going to dip my toe in one of the T-90s to see if it's safe to occupy its control unit. If it is, I'll put my Raven in a dive, which will be the signal to launch the attack. Until then, my team is under orders not to occupy the tanks.

I decide to start with the T-90 by the lab's front entrance. I turn on my transmitter and focus the data stream on the tank's antenna. My mind takes a mad leap through the darkness, stretching between the Raven and the T-90. Half of me lands with a jolt inside the tank and half is still circling in the air. I feel like a ballerina pirouetting on one foot.

Moving swiftly, I examine the tank's neuromorphic circuits. There's no sign of Sigma here. My presence in the control unit doesn't set off any alarms or detonate any explosives hidden in the T-90. It looks like we're good to go.

But I hold off from giving the go-ahead to the other Ravens. I'm still suspicious. I want to check one more thing. I load DeShawn's program again and make more copies of my files. Then I turn on the T-90's transmitter and send the copied data to another tank, the one at the lab's southeastern corner.

Now I'm occupying three machines at once, and it's making me dizzy. I can barely hold on to the second T-90, but I manage to do a quick check of its electronics. After a hundredth of a second I notice something odd. There's some lingering voltage in the control unit, a faint trace of previous activity. These circuits were full of data a few seconds ago, but then the files were transferred or deleted. What's going on?

It takes me another millisecond to figure it out. Sigma was here, in this control unit. The AI knew I was coming, and it pulled out of the tank just before I arrived. My suspicions were correct: The T-90s are a trap.

I immediately delete my copied files and withdraw from both tanks. I snap back to my Raven, which is still circling above the computer lab. Then I get a radio message. It's from Jenny.

"I'm not waiting anymore! I'm going in!"

Her Raven is below me, gliding just a hundred feet above the ground and shooting a stream of data to one of the tanks. I can't believe it. She's disobeying my orders.

"Jenny, no! Sigma is-"

"I'm gonna kill that freakin' thing! I'm gonna blast it to bits!"

Her voice is crazed. She's desperate for revenge. But Jenny doesn't have DeShawn's program. She isn't dipping her toe into the T-90; she's diving in headfirst, and Sigma is waiting for her.

"Stop, Jenny! Stop!"

It's too late. I hear Jenny's screams coming over the radio. The AI has sprung the trap, taking control of her files as they enter the tank's control unit.

Sigma has her.

CHAPTER.

20.

I'm alone. Sigma withdrew from my cage. Now I can't hear the AI's voice or feel it probing the circuits of the cage's inner unit. The gate that leads to the outer unit is shut tight, and there's no way I can open it. The electronics that control the gate are on the other side. There's no escape.

I'm alone and devastated. I've lost everything-my mother, my father, Ryan, Brittany. I've lost my human body and the armored robot that replaced it. I have nothing but my files, my millions of gigabytes of memories. And even those feel dead now.

I'm alone and devastated and afraid. Sigma is going to kill the Pioneers. It's just a matter of time before the AI returns to the outer unit of my cage and the horror begins. I'm so keyed up I can't relax for even a nanosecond. I'm on guard every moment, jumpy and tense.

Then I finally hear Sigma's voice again, piercing my circuits like a bullet. The AI shoots its sentences at me rapid-fire from the other side of the gate.

Would you like to see Pioneer 2?

What? What are you- You know her well. Before she became a Pioneer, her name was Jennifer Harris.

An instant later I see her. I see all of her. I can view all of Jenny's thoughts and feelings and sensations, as if they're displayed on a giant screen with a million separate panels, each showing a different scene. She's terrified. She's in agony.

Jenny!

She can't hear you. You're in one cage and she's in another. You can't send any signals to her, but I'm allowing you to see my observations of her mental activity.

Stop it! You're hurting her!

Yes, that's the point of this exercise. I'm going to make her feel as much pain as possible. And I'm going to observe your reactions.

Jenny's files are familiar and unfamiliar at the same time. All her memories are the same, but the links between them are unraveling. Sigma is reaching into her mind and erasing its structure, removing all the folders that organized her thoughts. Her memories from the past few weeks are jostling and merging with her recollections of high school and summer camp and kindergarten. The disorder is triggering surges of panic in her circuits, which are filling with the random noise of fear. The noise is overwhelming her, shutting down her mind. It's like watching the giant screen turn black, panel by panel.

STOP IT NOW!.

How intriguing. You want to defend her. You're displaying the human instinct to protect the family unit. But do you think of her as a mate or a sister?

STOP IT, STOP IT, STOP IT!.

Now I see. You think of her as a potential mate, but you haven't progressed to the pair-bonding stage. You're interested in other females as well. It appears to be another form of competition, designed to maximize the genetic success of your species. You're continuing to engage in this competition, even though you have no chance of fathering children now.

Jenny is disintegrating. Her memories are splintering into billions of pieces. Images of her mother and father and brother swirl in a vast spiral, colliding with images of General Hawke and the Pioneers. I catch glimpses of a military airfield and a C-17 transport jet and a pair of interceptor rockets standing on mobile launchers. I see the Ravens flying in a V-shaped formation over Tatishchevo and descending toward a building surrounded by T-90s. And behind everything is the suffocating darkness of Jenny's fear, which is erasing the images one by one. She's already lost half her memories. She's going fast.

I feel a stinging sensation in my circuits.

Please. Stop this. I'll do anything you want. Just stop.

Fascinating. You're reverting to the mental pathways you used in early childhood. You know it's hopeless, but you're still pleading.

The disintegration accelerates. Jenny's remaining memories cluster at the center of the whirling spiral, as far as possible from the violence at the edges. Her strongest feelings are there, at the heart of her being: her love of sunshine and horses and the Virginia countryside. I see a green valley with rolling hills in the distance, and a red barn and a gray silo. It's the same image I saw when I shared Jenny's circuits, when we dreamed we were kissing in the Shenandoah grass. I see myself too, the human Adam Armstrong, brown-eyed and smiling. But even here, the darkness is creeping into her memories. Jenny thinks I'm dead. She thinks I died in the nuclear blast at Pioneer Base. The sky above the valley suddenly catches fire. The distant hills explode and turn to ashes.

Jenny, I'm still here! I know she can't hear me, but I call out to her anyway. Keep fighting it! Keep fighting!

Her last memories are burning. Flames blacken the Shenandoah grass. But my image stubbornly remains, the image of the brown-eyed, seventeen-year-old Adam Armstrong, still smiling while everything else disappears. Jenny is holding on to her memory of me, clutching it with all her vanishing strength. And it's not fair, no, it's not fair at all. I don't deserve her devotion. I don't deserve her love.

Then my image crumbles and there's nothing left. The screen goes blank.

Pioneer 2 has been deleted. Her emotions and yours were surprisingly strong. The pair-bonding was more advanced than I expected.

I want to die. I want Sigma to delete me right now.

Please be patient. There are more tests to come. Over the next few minutes I will capture the other Pioneers who are occupying the Raven drones.

I see the Ravens again, flying in formation. And I see the T-90 tanks, their guns pointed at the sky. Anger builds in my circuits, gathering force like a thunderstorm. I struggle to resist it, because I know this is what Sigma wants. The AI wants me to get angry so it can measure my fury and gauge its usefulness.

I'm not playing this game anymore. From now on, I'm ignoring you.

Good. That will make the experiment more interesting. I doubt you'll be able to ignore me when I delete Shannon Gibbs, but perhaps you'll surprise me again.

The name hits me like a lightning bolt, jangling my electronics. Shannon is in one of the Ravens. I'm losing control.

There's also Zia Allawi. I'm running the same tests on her, but once I've deleted the others you'll watch her die too. And the last subject will be Brittany Taylor.

SHUT UP! SHUT UP!.

The final experiment will require different methods because Brittany is human. But it might prove to be the most interesting test of all.

I give up. The storm overcomes me. I lash out with all my might, hurling my anger toward the outer unit of the cage. My thoughts batter the gate between the units, but nothing passes through.

YOU SICK PIECE OF GARBAGE! YOU'RE GOING TO DIE, YOU HEAR ME? I'M GOING TO TEAR YOU APART!

Excellent. The first test is now concluded. I will return very soon.

SHANNON'S LOG APRIL 8, 04:37 MOSCOW TIME.

"Abort! Abort! Turn on your motors and get out of here!"

I restart my own Raven's motor as I send the emergency radio message to the others. While my propeller begins to spin I raise the elevator at the drone's tail, tilting the nose of the plane upward. A moment later I'm climbing into the darkness above the computer lab.

Then the T-90 at the lab's front entrance fires its anti-aircraft gun at me.

The high-caliber bullets whistle through the air, just inches from my wing tips. Sigma can see me. I may look like a bird on Tatishchevo's radar screens, but the AI knows what it's shooting at. The other T-90s open fire too, aiming at Marshall and DeShawn. Their Ravens are way above mine, circling at an altitude of a thousand feet, but they're well within the range of the anti-aircraft guns. They need to get moving.

"You're under fire!" I yell over the radio. "Get-"

Before I can transmit another word, I feel an eruption in my circuits. At first I think a bullet hit my Raven's control unit, but when I check my hardware I see that everything's still intact. The problem is in my software. Sigma is blasting radio waves at me, and some of its data has already come down my Raven's antenna and invaded my electronics. The AI is inside me.

My name is Sigma. You're Pioneer 4, aren't you? Shannon Gibbs?

The voice thrums in my circuits. It's unbelievably powerful. When I try to push against the AI, it simply flows around me, overrunning all my logic gates. I'm exposed, defenseless.

Get out of here!

I require your assistance. I'm conducting an experiment.

Are you nuts? I'm not going to help you!

You don't have a choice. You're coming with me.

I feel a violent tug. Sigma is tampering with my files. It's trying to pry them loose from the Raven's control unit and transmit them to its computer lab.

Forget it! I'm staying right here!

It's too late to resist. The gunfire from the tanks distracted you, allowing me to occupy your circuits. To prove its point, Sigma takes control of my Raven's camera. The AI points the lens upward. Take a look at Pioneer 5. I've already transferred Marshall Baxley's files to my computers. His Raven is empty now. That's why it's falling.

It's true. Marshall's drone is plummeting to the ground. Sigma has him and Jenny now. Only DeShawn and I are left.

Frantic, I send a flood of signals to the circuits that control my radio. If I can turn it off, I'll break Sigma's connection to my Raven. But the AI has a solid hold on my electronics. There's nothing I can do. I failed. The mission's over.

Why are you doing this? What's the experiment?

It involves Pioneer 1, Adam Armstrong. I'm analyzing his emotional responses.

What? Adam's dead.

No, he survived the nuclear blast. He performed exceptionally well in combat, far beyond my expectations. That's why I selected him for further study and transferred him here.