CHAPTER 1

It would be the disaster of their generation, like the fall of the Twin Towers or Kennedy’s assassination. Sandra Kelley was one of the early responders, one of the first to see the stadium lying crushed, torn apart as if by an angry giant. She was less than two years out of police academy, a junior officer still doing patrol on the night shift. She had seen victims of traffic accidents, so she wasn’t entirely green, but nothing could have prepared her for this.

It seemed as if every police car, ambulance, and fire truck in the city had been routed to Broad and Pattison, but it wasn’t nearly enough. There had been a Wasted Euth concert at Lincoln Financial Field that night, so there were crowds of gawkers to control, and the number of injured in the parking lot alone was more than they could handle. Debris lay scattered everywhere.

Most of the light poles in the parking lot were still intact, but the stadium wreckage itself was dark, an unexpected hole where once 2000-watt lights had blazed out into the night. The sky was overcast, a brooding bank of clouds that hid the stars and seemed to press down on the city.

Sandra dialed her dad’s phone for what must have been the tenth time. The call went straight to voice mail, just like every other attempt. Her voice was shaking badly. “Dad, please call. Please get this. Tell me you weren’t at the game.”

She called her mom’s phone next. No answer. She had left three messages already, but she left another one anyway. “Mom, it’s Sandra. Please call. Dad was there, wasn’t he? He had tickets. I don’t remember when, but I think it was tonight. He invited me, but I was on duty . . .” She choked on the words and clicked off.

She weaved her way around battered blue plastic seats, strewn across the parking lot alongside unrecognizable pieces of mangled metal and concrete. There were bodies, dozens of them. Some of them were whole. Others were not. She stopped, doubled over, and vomited on her shoes.

Her sergeant took one look at her face and pointed her toward crowd control. Facing away from the stadium as much as possible, she and a dozen other cops shouted people back and strung police tape to cordon off the whole area. The first moment she could, she pulled her phone out of her pocket and called her parents again. Nothing.

“Here.” Another cop pushed a water bottle into her hands. It was Nathan, from her class at the academy. She took the bottle gratefully, swished some water in her mouth, and spat it onto the pavement. It cleared some of the taste of vomit from her mouth, but not the acid taste of fear. She felt jittery and light-headed, like she was on some kind of uppers or a massive dose of caffeine.

“Thanks,” she said, handing back the bottle.

“Keep it,” Nathan said. He was blond and tall, with athletic good looks. The uniform fit him well. She had had a bit of a crush on him back in the day, but he had fallen for a cadet named Danielle instead, and they’d married a week after graduation.

Sandra tried her phone again, but with no result. Nathan studied her face. “You know somebody who was here?”

She nodded, swallowing hard. “My dad. He used to take us all the time, when we were . . .” Her voice cracked, and she pressed her lips together, holding back tears.

“They’ll find him,” Nathan said. “Don’t give up hope.”

She smiled as best she could and nodded her thanks. Heavy earthmoving and construction equipment rolled in, bulldozers and front-end loaders and cranes. Her sergeant pulled her back to help with search and rescue. There were people trapped under eighty-ton blocks of concrete, but no one seemed to agree about the best way to move them safely. She found herself in crews of strangers, moving what rubble could be moved by hand. She was tired, bone tired, but she knew she couldn’t stop. People’s lives depended on the work she was doing. And one of them just might be her father.

The FBI rolled in and added to the confusion, waving their badges and trying to preserve the crime scene at the same time rescue workers were tearing it apart. No one seemed to know quite who was in charge. Without direct orders, Sandra did whatever she could, directing EMTs with stretchers, soothing panicked family members, and checking press badges for the reporters that swarmed the site like flies.

While she did all this, she recorded everything she saw. Like most police officers, Sandra wore eyejack lenses, the raw footage feeding into a huge database that could be merged into a single, time-tagged, three-dimensional image of the site. The detectives and bomb experts would study the data for clues as to what had happened. Was it a terrorist attack? Or just a catastrophic engineering failure? Feedback to her lenses told her which views and angles were under-represented, encouraging her to aim her vision in directions that would help fill in the holes.

The news she was getting through her phone told her the media was already pointing fingers at the Turks. With American forces in Poland and Germany blocking the Turkish advance, and the Turkish navy controlling access to the Mediterranean, this was hardly a surprise. The talking heads called it a Turkish attack on American soil, comparing it to Pearl Harbor and calling for war. The Turkish president officially denied it, and it was hard for Sandra to see what they would gain from such a move. Though she supposed terrorists operated under a different set of assumptions than most people.

She hadn’t seen her sergeant in hours, so she just wandered the site, joining gangs of workers where she saw a need. She queried the central database to see what views had not yet been covered and headed in those directions, trying to provide as much data as possible to the professionals whose job it was to make sense of it all. All around her, there was the horror of death, so much death that she could hardly take it in. She felt emotionally detached, floating in a protective bubble her mind had formed around the experience. Her awareness collapsed to simple tasks. Step over the twisted metal. Help lift the concrete slab. Check GPS and shift viewing angle to forty degrees.

Her father still didn’t return her calls.

“Hey! Officer! Could you give me a hand?”

Sandra turned to see a young man in a black Robson Forensic cap waving to her. He was struggling to haul two black hard cases on wheels over the debris-strewn ground.

“Finally,” he said. “What’s a guy got to do to get a girl to pay him some attention?”

She narrowed her eyes, not in the mood for humor. “What do you want?”

“Could you take one of these? This is really a two-person job.”

One of the cases was the size of a large suitcase; the other was big enough to hold a bass fiddle. Sandra took the smaller one. “What is all this stuff?”

“ID equipment,” the forensic tech said, puffing as he hauled on the larger case.

Sandra imagined a lab on wheels, blood testing and DNA, taking samples from the thousands of bodies and determining their identities. “You can do that in the field?”

The tech didn’t answer. They had reached a flat area with a minimum of debris. “This will do,” he said. “Open that one up, will you?”

Inside she found telescoping poles, wires, and what looked like a large security camera. “What kind of ID kit is this?” she asked.

“The best kind, I hope,” the tech said. He opened the larger case. Sandra didn’t understand at first what she was looking at. The case seemed to be stacked with dozens of small electric fans.

The tech circled around to the smaller case and pulled out lengths of pipe, assembling them with ease. In short order, he constructed a ten-foot tripod stand with the camera device on top. From the bottom of the case, he extracted a box with levers and a long antenna, like a remote control. “Stand back,” he said.

He flipped a switch, and the larger case started rumbling. It vibrated visibly, chattering against the concrete.

“What—” Sandra started to say, but she was interrupted by a sound like the buzzing of a hundred angry bees. Out of the case rose a formation of two dozen quad-rotored helicopters, each the size of a dinner plate. They dipped in unison, shearing off to the right just as a second formation rose up to take their place. Each formation was a perfect rectangle, six copters by four, flying inches apart and moving as if locked together. At a cue from the tech, they left their places and flowed into a new formation, twenty-four wide by two deep.

He pressed another button, and the quadcopters shot off toward the ruined stadium, doing twenty or thirty miles an hour, eight feet above the ground. Several people shouted or leapt away, but the copters veered effortlessly to miss all obstacles, breaking out of formation or angling their flight as necessary. Sandra looked after them in awe. In the darkness, their LED lights swirled like a swarm of fireflies. Above her head, the device that looked like a camera came alive, smoothly slewing back and forth as if aiming at each of the receding quadcopters in rapid succession.

Some of the people nearby threw dirty looks their way. A few picked themselves off the ground after diving to avoid the copter brigade.

Sandra forgot her astonishment and wondered if she’d just been tricked. She had no idea what this guy was doing, but it wasn’t forensics. Was he a reporter? Or was he a terrorist, out to destroy evidence or make a secondary attack?

She undid the snap that held her pistol in its holster. “Put the remote down,” she said.

He looked bewildered. “But—”

“Now!”

He dropped the remote and held up his hands. “You don’t understand—”

“What kind of stunt are you trying to pull? You said this was ID equipment.” She reached for her radio to call him in.

“It is!” he said. “The copters have RFID readers on board. I told you the truth.”

She paused. She would make a fool of herself if she called in a real CSI.

“Let me see your ID,” she snapped.

“Honest,” he said.

“ID.” She held out her hand.

Sheepish, he dug around in a pocket and handed up a laminated card. It was a University of Pennsylvania student ID.

“You’re a student?”

He looked offended. “I’m an engineering doctoral candidate in robotics and sensory perception.”

“Put your hands down.”

He put them down. “I’m allowed to be here.”

“What about the cap?”

He took it off and looked at the logo. “Oh,” he said. “Some of the forensic outfits hire us sometimes.”

“And who gave you permission to loose a fleet of helicopters in a crowded search and rescue scene?” she said.

“It’s a swarm, not a fleet,” he said. “Look, most of the people who died out there have cards in their wallets with RFIDs in them. Credit cards, gas cards, SEPTA cards. They work with magnetic resonance; illuminate them with a burst of radio energy, and they fire back a signal with a number on it. With the right databases, those numbers can be turned into people’s names. The quadcopters tag the number and the GPS coordinates, and boom: we have a map of the positions and IDs of every person on the site. Well, nearly. A lot of them anyway.”

Sandra was cooling down now that he seemed to be legit. She holstered her weapon. “What’s the camera for?”

“This?” he said, pointing up at the device on the tripod. “That’s the radio transmitter. I have to use a pretty narrow beam to get a strong enough return signal through the rubble. The copters can’t carry one, so I mount it here and coordinate them. Most RFID readers are two-way, but I had to split it up: the transmitter here to pulse the energy at each spot on the ground, and the copters at the right spot at just the right time to detect any returns.”

“And you had permission to do this?”

He winced. “Sort of.”

“What does ‘sort of’ mean?”

“The chief told me I could do whatever harebrained experiment I wanted as long as I got out of her way.” He gave an awkward smile. “I guess I charmed her with my rugged good looks.”

Sandra smiled in spite of herself. The tech wasn’t rugged or good-looking, not by anybody’s definition. He was short and soft, with a thick face, glasses, and a hint of a mustache. His skin was a light, mottled brown, and his hair could have used a trim months ago.

“Oh, fine,” he said. “I see how it is. You like them tall and blond. Blue eyes, probably. Flawless skin, Swedish accent—I know the type.”

“I’m just doing my job. You’d better not be lying about the chief, because I’m going to check.” She glanced back at his ID card. “Your name is Angel?”

“An-HEL. The g is pronounced with an h sound.” He rolled his eyes.

Her smile vanished. “What?”

“I know what you’re thinking. Who would name a boy ‘Angel’? Typical American. I’ll have you know Angel was the fifth most popular name for boys born in Mexico last year.”

“Is that where you’re from?” she asked. “Mexico?”

“Born and bred.” He lifted his chin high. “Spent my whole life in San Antonio, until last year.”

Sandra paused. “Isn’t San Antonio in the United States?”

“There you go again, with your prejudicial comments,” Angel said. “Only Americans think it’s in the United States.”

This time she caught the sparkle in his eyes. “Are you serious?”

He grinned, breaking the tension. “I’d say about twenty percent of the time.”

She wanted to punch him. She couldn’t tell when he meant what he was saying and when he was just messing with her. In her current state of high tension, she didn’t find that funny. On the other hand, she was having a conversation, and having a conversation meant not looking at the scene around her, expecting to stumble over her father’s body at any moment.

The angry buzzing sound grew louder, and she turned just in time to see the swarm of quadcopters bearing down on her. She gasped and ducked, but the copters reined up short, breaking off into groups of four. Each group of four wheeled up to Angel, hovering around him for a few moments before banking away again. He snapped open a laptop and typed rapidly.

“It’s working!” he said, the astonishment evident in his voice.

“You’re surprised? Haven’t you tried this before?”

“In the lab, sure, but not in real life.”

“You covered the whole site already?”

“No, not even close.” As the last foursome left him, the copters slid into formation and shot away toward the wreckage again. “It’ll take hours to cover everything. But that’s a lot better than days, maybe weeks, of dozens of techs with handheld readers doing the same thing. The information won’t be conclusive; people will still have to confirm each identification, actually look at each body. But as a preliminary map, it should save a lot of effort and let family members know about their loved ones more quickly.”

He rotated the laptop to show her the screen. It was an aerial map of the site, flanked by Pattison Avenue and Hartranft Street. One corner was peppered with yellow dots. Angel zoomed in on that corner, and the dots bloomed out into numbers.

“Each of those points is a person. Probably,” he said. “There are RFIDs in other things, too.”

“And from that you know who they are?”

“Well, I don’t,” he said. “I don’t have access to those databases. But the police do, you can be certain, and if there are any they don’t have, the feds can get them.”

Sandra studied the design the dots made on the screen, swooping in zigzagging curves. It didn’t look random. “Why does it make a pattern?”

Angel shrugged. “I don’t know.”

She thought about what her dad would say, seeing a pattern like that. “It might be important,” she said. “If things were thrown around in a recognizable pattern, we might be able to determine what caused this, maybe even track down the source.”

Another shrug. “I work in a robotics lab, but I’ll tell you one thing; this was no bomb.”

She cocked her head at him. “What do you mean?”

“There was no fire,” he said. “Nothing’s burned. And look at how the stadium collapsed—it looks more like it fell in on itself than like it was blown out. Most of the rubble is piled up inside, on the playing field. More like an earthquake. Or a sinkhole.”

He was right. It was obvious, now that she thought about it. There was plenty of debris in the parking lot, but it looked more like it had been pushed by the force of the falling stadium walls, not like the walls themselves had been blown out. But there had been no earthquake; at least not that anyone was reporting in the news. “Maybe there were a lot of smaller charges placed at key spots,” she said. “Arranged so that the walls would fall in and kill as many people as possible.”

Angel nodded, thoughtful. “Hey,” he said, “if we know where the people are now, and where they were originally sitting, maybe we could draw lines from their starting point to where they ended up. We could track the vectors of force.”

He was getting excited, but all she could think about was the image of her father’s body being blown out of his seat. She felt sick and put her hand over her mouth.

A female cop ran up to her, dark hair blown back in the wind. It was Danielle, Nathan’s wife. “Sandra,” she said, “you’ve got to come now.”

“What is it?”

“I think it’s your father.”

Sandra’s mind rebelled at the words. She wanted to punch Danielle in her pretty mouth for daring to say such a thing. “Dead?”

Danielle didn’t answer, but her eyes told Sandra everything.

Sandra followed her at a run to where Nathan stood over a body on the ground. His shoulders were hunched, his eyes dead. He was holding a black leather wallet, worn and familiar. Sandra looked at the wallet, refusing to look down, terror gripping her throat.

She took the wallet and flipped it open. Her father’s face stared up at her from his Pennsylvania driver’s license, but she checked the name anyway. Jacob Kelley. She shook her head, trying to process what she was seeing, the information somehow failing to sink in, even though she’d been expecting it now for hours. She shook her head, trying to push the evidence away, wishing for a return to uncertainty, when it was still possible that he hadn’t been here.

Finally, she looked down. Her father lay on the pavement as naturally as if he’d fallen asleep there.

“I’m sorry,” Nathan began. She waved her hand to fend off his words, and he trailed off. He stood there, awkward, not knowing what to say. Danielle put a hand on her arm. Sandra turned and buried her face into the coarse, blue fabric of Danielle’s shoulder. She felt like she ought to cry, but the tears didn’t come. Danielle stroked her hair, while Sandra took in big gulps of air, like she was drowning.

Her phone rang.

The noise startled her. She reached for it automatically, and then nearly threw it away. She’d been waiting for it to ring all night, and now, when it finally did, it was too late. The automatic movement brought the screen up to her eyes, however, and she saw the number. It was her father’s number.

She answered.

“Sandra?” Her father’s voice was warm and strong and sweet and utterly recognizable.

“Dad?”