"Dr. Simcoe, what happened?" asked a man.

Lloyd was getting sick of the question. "I don't know. Can you operate the PA?"

The man looked at him; evidently Lloyd was using a North Americanism the fellow didn't know.

"The PA," said Lloyd. "The public-address system."

The man's blank look continued.

"The intercom!"

"Oh, sure," he said, his English harshened by a German accent. "Over here." He led Lloyd to a console and flipped some buttons. Lloyd picked up the thin plastic wand that had the solid-state microphone at its tip.

"This is Lloyd Simcoe." He could hear his own voice coming back at him from the speaker out in the corridor, but filters in the system eliminated any feedback. "Clearly, something has happened. Several people are injured. If you yourself are ambulatory — " He stopped himself; English was a second language for most of the workers here. "If you yourself can walk, and if people you're with can walk as well, or at least can be left, please come at once to the main lobby. Someone could have fallen in a hidden place; we need to find out if anyone is missing." He handed the microphone back to the man. "Can you repeat the gist of that in German and French?"

"Jawohl," said the man, already switching mental gears. He began to speak into the mike. Lloyd moved away from the PA controls. He then ushered the able-bodied people out of the office into the lobby, which was decorated with a long brass plaque rescued from one of the older buildings that had been demolished to make room for the LHC control center. The plaque spelled out CERN's original acronym: Conseil Europeenne pour la Recherche Nucleaire. These days, the acronym didn't actually stand for anything, but its historical roots were honored here.

The faces in the lobby were mostly white, with a few — Lloyd stopped himself before he mentally referred to them as melanic-Americans, the term currently preferred by blacks in the United States. Although Peter Carter, there, was from Stanford, most of the other blacks were actually directly from Africa. There were also several Asians, including, of course, Michiko, who had come to the lobby in response to the PA announcement. Lloyd moved over to her and gave her a hug. Thank God she, at least, hadn't been hurt. "Anybody seriously injured?" he asked.

"A few bruises and another bloody nose," said Michiko, "but nothing major. You?"

Lloyd scanned for the woman who had banged her head. She hadn't shown up yet. "One possible concussion, a broken arm, and a bad burn." He paused. "We should really call for some ambulances — get the injured to a hospital."

"I'll take care of that," said Michiko. She disappeared into the office.

The assembled group was getting larger; it now numbered about two hundred people. "Everyone!" shouted Lloyd. "Your attention, please! Votre attention, s'il vous plait!" He waited until all eyes were on him. "Look around and see if you can account for your coworkers or office mates or lab staff. If anyone you've seen today is missing, let me know. And if anyone here in the lobby requires immediate medical attention, let me know that, too. We've called for some ambulances."

As he said that, Michiko re-emerged. Her skin was even paler than normal, and her voice was quavering as she spoke. "There won't be any ambulances," she said. "Not anytime soon, anyway. The emergency operator told me they're all tied up in Geneva. Apparently every driver on the roads blacked out; they can't even begin to tally up how many people are dead."

CERN was founded fifty-five years previously, in 1954. Its staff consisted of three thousand people of which about a third were physicists or engineers, a third were technicians, and the remaining third were split evenly between administrators and craftspeople.

The Large Hadron Collider was built at a cost of five billion American dollars inside the same circular underground tunnel straddling the Swiss-French border that still housed CERN's older, no-longer-used Large Electron-Positron collider; LEP had been in service from 1989 to 2000. The LHC used 10-Tesla dual-field superconducting electromagnets to propel particles around the giant ring. CERN had the largest and most powerful cryogenic system in the world, using liquid helium to chill the magnets to just 1.8 Celsius degrees above absolute zero.

The Large Hadron Collider was actually two accelerators in one: one accelerated particles clockwise; the other, counterclockwise. A particle beam going in one direction could be made to collide with another beam going in the opposite direction, and then—

And then E=mc², big time.

Einstein's equation said simply that matter and energy are interchangeable. If you collide particles at high enough velocities, the kinetic energy of the collision may be converted into exotic particles.

The LHC had been activated in 2006, and during its first few years of work it did proton-proton collisions, producing energies of up to fourteen trillion electron-volts.

But now it was time to move on to Phase Two, and Lloyd Simcoe and Theo Procopides had led the team designing the first experiment. In Phase Two, instead of colliding protons together, lead nuclei — each two hundred and seventeen times more massive than a proton — would be rammed into each other. The resulting collisions would produce eleven hundred and fifty trillion electron volts, comparable to the energy level in the universe only a billionth of a second after the big bang. At that energy level, Lloyd and Theo should have produced the Higgs boson, a particle that physicists had been pursuing for half a century.

Instead, they produced death and destruction on a staggering scale.

Gaston Beranger, Director-General of CERN, was a compact, hairy man with a sharp, high-bridged nose. He had been sitting in his office when the phenomenon occurred. It was the largest office on the CERN campus, with a long real-wood conference table directly in front of his desk, and a large, mirror-backed, well-stocked bar. Beranger didn't drink himself — not anymore; there was nothing harder than being an alcoholic in France, where wine flowed with every meal; Gaston had lived in Paris until his appointment at CERN. But when ambassadors came to see what their millions were being spent on, he needed to be able to pour them a glass without ever once showing how desperately he would have liked to have joined them.

Of course, Lloyd Simcoe and his sidekick Theo Procopides were trying their big experiment in the LHC this afternoon; he could have cleared his schedule to have gone and watched that — but there was always something major going, and if he went to watch every run of the accelerators he'd never get any work done. Besides, he needed to prepare for his meeting tomorrow morning with the team from Gec Alsthom, and—

"You pick that up!"

Gaston Beranger had no doubt where he was: it was his house, on Geneva's Right Bank. The Ikea Billy bookcases were the same, as were the couch and the easy chair. But the Sony TV, and its stand, were gone. Instead, what must have been a flat-panel monitor was mounted on the wall above where the TV used to be. It was showing an international lacrosse game. One team was clearly Spain's, but he didn't recognize the other team, clad in green-and-purple jerseys.

A young man had come into the room. Gaston didn't recognize him, either. He had been wearing what appeared to be a black leather jacket, and had thrown it over the end of the couch, where it had slipped down to the carpeted floor. A small robot, not much bigger than a shoebox, rolled out from under an end table and started toward the fallen coat. Gaston pointed a finger at the robot and barked, "Arrêt!" The machine froze, then, after a moment, retreated back under the table.The young man turned around. He looked to be maybe nineteen or twenty. On his right cheek there was what seemed to be an animated tattoo of a lightning bolt; it zigzagged its way across the young man's face in five discrete jumps, then repeated the cycle over and over again.