Carlo snorted. "Obviously. Now come on!"

Chapter Thirty-Four.

They flew through the door and under an arch, and plunged upward into a maze of intricate passages, a stampede of feet closing in behind.

Carlo swung around. "I'll discover what I can about your father, rescue him if necessary. Through the red door!"

They burst into a long room that smelled of gasoline and car wax. It might have once been the stables of the school, but it now seemed to be where they stored a collection of rare and antique cars.

Standing calmly in front of them was a large woman with a wispy tangle of white hair. She barely looked up as she tugged on a pair of leather racing gloves. Carlo whipped off some words in Italian and handed her a thick brown envelope. The woman nodded slightly. Becca translated. "He told her we need a ride out of here. Fast."

Wade thought, Is there anything Becca can't understand?

The woman unhooked a set of keys from a collection hanging on the wall and, despite her bulk, slipped gingerly into the driver's seat of a sleek gold coupe.

Darrell gasped. "Holy cow! It's a mint 1976 Maserati. I love those!"

"Keep the diary safe," Carlo said, looking directly at Becca. "It must be taken from here now, but I will come for it later. The Order will stop at nothing."

"How do they always know where we are?" asked Lily.

"Give me your computer and your phone," Carlo said. "The Order has military-grade tracking technology. Take this instead." He slipped his hand into a pocket and removed a brand-new smartphone. "It's encrypted so they won't be able to track you at first. For emergencies only, understand? All calls under two minutes. Also . . . keep it charged. Here." He passed Lily a charger.

"Thank you!" said Becca, helping pry Lily's fingers off her tablet.

With a horrible thump, the red door buckled. One hinge popped off.

"The Order's here," said the girl. "Time for our friends to leave. Studenti, vieni!"

All at once, a side passage filled with the sound of thundering feet, and a stream of fifty or more fencing students poured into the garage.

"Ready?" Carlo called to them.

"Ready!" they sang in unison.

"Take positions," said the girl. The students flattened themselves against the walls on either side of the iron door, weapons raised.

"Go!" Carlo yelled to the driver. "Buona fortuna, kids. You will see me again!"

They dived into the car just when the door broke open. At least a dozen men in ski masks bounded in, wielding pistols with silencers.

As if they had been waiting their whole lives for this, the armed students descended on the thugs from behind, catching them off guard. The room exploded in a clash of blades and muffled gunfire.

"Cinture di sicurezza!" the driver shouted.

Wade didn't need a translator to tell him to strap on his seatbelt. The Maserati roared to life, drowning for an instant the mayhem in the room. While the students lunged furiously across the floor, keeping the thugs from appraching the car, a wide garage door flipped up into the ceiling. Daylight poured in from the top of a long ramp.

With its driver laughing at the top of her lungs, the vintage Maserati fishtailed up the ramp and bounced wildly onto the busy streets of Bologna.

They had escaped.

Chapter Thirty-Five.

Paris, France March 12th 6:12 p.m.

THWACK-K-K!.

The noise-canceling headphones flattened Galina's hair, so she rarely used them. Today, however, it was necessary.

THWACK-K-K!.

At 440 feet per second, the sound of a titanium arrow striking its target made the walls of the basement gallery shudder. Removing the headphones, she stared through the crosshairs at the tiny dot of red light centered on the target, flipped the lever alongside the barrel to Silent, and fired a third round.

Fhooo-wit! A bare whisper with only a slight decrease in speed-427 feet per second-and again the arrow pierced the target dead center. Yes. This was the setting she would use.

As usual Ebner was lurking around somewhere. He was rarely far away unless she sent him to fetch something. She heard his shoes scuff the floor behind her.

"The standard handgun bullet travels at eight hundred seventy feet per second," Ebner said. "Which translates to some six hundred sixty miles per hour. These arrows move at, say, half that speed-"

"The crossbow has a long and illustrious history as a hunting weapon," Galina said. "These shafts are lightweight, hollow."

Ebner glanced at the target. Three arrows dead center, stunningly accurate, a tiny teardrop of liquid sliding from each hole. He had heard about the shooting range under the streets of her French office complex, though he had never been allowed inside. She had so many estates and offices and rooms here and there and everywhere, it was a wonder she could keep them straight. But then, Galina was remarkable for that, as in so many other things.

"We are in the city. What can you hunt here?" he asked.

She turned and glared at him, imagining his head balancing an apple on it. "People. What else? The reporter digging into the Le Monde murder arrives home every evening after a stroll by the river. Tonight, he will not arrive home."

She took aim for a fourth time when a phone rang in the vicinity of Ebner's sunken chest. She glowered at the interruption as he fumbled to answer it.

"Ya?" he said. "No . . . no, no! You incompetent fools!"

Galina lowered the crossbow without removing the arrow. "What is it now?"

"The computer signal has been lost. The school was on alert. We have casualties. The children have escaped Bologna."

Galina whipped the crossbow up to her shoulder and fired the final arrow downrange without taking aim. It struck the target as the others had, exactly in the center. "Prepare the yacht and my jet. I must be ready to move at any moment."

"Of course, Miss Krause. My apologies. The next time-"

"There will be no next time for you, Ebner von Braun. Stop the children immediately, or I shall stop you."

With three swift gestures, she collapsed the crossbow into a fraction of its size and set it in a small case lined with fin-tipped titanium arrows. Slinging it over her shoulder, she stepped into an elevator, saying, "Street level." Ebner hurried in behind her before the doors closed.

"The Australian Transit is a success," he said. "Our office in Sydney has received the mice. One day early."

"Only one day?" she said, a taste of bitterness on her lips.

"Yes, Miss Krause. Baby steps," he said. "Shall I instruct the laboratory to proceed with the Spanish Experiment?"

She was silent as the elevator rose. One-hundred-and-ninety-seven days away was now one hundred and ninety-five. The doors slid open on a wide hallway filled with mirrors and elaborate Rococo paintings of hunting scenes framed in gold. She strode toward a set of glass doors at the far end of the hall. Ebner followed like a good puppy.

"They promise greater success this time," he added. "They are much closer to cracking the equations."

"Tell them to proceed. Inform me when you have results."

But until then, she thought, the fool children were misplaced in Italy, and she would have to go there, after all. Her mind agonized over the loss of the children, but her bigger concerns were the Order's forces. They made mistakes. Back in the sixteenth century, Grand Master Albrecht von Hohenzollern would have been appalled at their incompetence and would have dealt with them harshly.

Failure meant beheading.

This was a different era, of course. She would have to make do. Money helped, and she had nearly unlimited funds. What she really needed was time. But sand falls only one way in an hourglass.

She knew a sole genius of particular talents to complement her own, one to help her plan move more swiftly, but, sadly, he was unavailable. Ebner was as close as she had gotten. And she had to put up with his lurking and leering.

Galina opened the glass doors and stepped outside onto a flight of stairs leading down to a grand public square. Sunset in one hour.

Towering over Paris's Place de la Concorde was the great Luxor Obelisk. Erected on the spot where the guillotine once enacted its vengeance, this priceless gift from Egypt was now a smog-enveloped inconvenience for motorbikes and cars to whiz around like so many toys. It was a shame that beheadings were no longer popular.

"I will wander by the Louvre before I stroll the riverbank," Galina said. "I must think."

Ebner followed her down two steps, a third.

She stopped and turned. "And by that, I mean alone."

Chapter Thirty-Six.

The Maserati sliced its way through the Italian hills like a sharp knife through oversteamed broccoli.

Unable to avert his eyes from the road, Wade's heart thumped so wildly it pushed his lungs up into his throat, where he was pretty sure they stopped working.

"Wade, you all right up there?" asked Lily.

"Uh . . ."

The driver laughed and nodded to the back. "C'e un cesto. Mangiate!"

"A basket?" said Becca.

Darrell tugged at something behind his seat. "Right here. A picnic basket full of stuff. Bread, cheese, salami. Even Cokes!" He dove into it, passed it around, and the kids stuffed themselves for the first time in hours. Despite the driver sending the car squealing around a hairpin and onto a straightaway at a speed of what had to be well over a hundred miles an hour, Wade managed to wash down a hearty cheese and salami sandwich with strawberry-flavored mineral water.

"Better. Much better," he said. He turned to see Becca shaking her head at the diary. "What did you find?"

"Something unhelpful," she said. "Listen. This is from before the whole Teutonic Order thing."

As we leave the island, our precious cargo lashed to the deck of the ship, Nicolaus passes me a small scrap of paper. "To add to the diary."

"What is it?" I ask.

"The man we met . . . he shared these numbers to explain how the device made the impossible possible. Hans, what do you think?"

The winches and pulleys of my brain twist and stall as the ship sails west. Finally, I begin to see the significance of the numbers.

Becca held out the diary to Wade. Her hands were trembling. "I don't know who 'the man we met' is, but can you make sense of this?"

The car was cruising quite calmly-for the moment-as Wade studied the yellow, weathered page and saw the following: ds2 = -c2dt2 + dl2 + (k2 + l2) (d2 + sin2 d2) "Algebra . . ." He puzzled over the sequence of letters and numbers, wondering at first if algebraic symbols were even around when Copernicus lived and wishing he knew more about the history of mathematics.

Dad would know.

Wade did his best to prod the winches and pulleys of his own brain and think like his father, but it wasn't working. Worry over the man's fate and the possibility of their own imminent death in Italian traffic made it impossible to focus.

He tugged out his father's student notebook. "This formula is way beyond me. In fact, I think it's actually called a metric. Maybe Dad wrote about something in his classes with Uncle Henry . . ."

The car accelerated swiftly now on a multilane highway. On their right, the sun had begun to set behind the hills. The Mediterranean lay beyond them.

As Wade turned the scribbled pages of his father's journal, he couldn't stop imagining what was happening back in Berlin. His eyes glazed over. Dad in a cell? Or worse.

"Wade?" Becca said, leaning over.

"Right. Sorry." He focused, searched the pages, then stopped when he read one particular notation. "Quantum physics? They didn't know about any quantum physics in the sixteenth century."

"What are you saying-" Darrell started.

Wade held up his hand for quiet. He turned one more page, checked the diary again, then finally shrugged. "The formula, or one quite like it, is actually in Dad's journal. But I don't see how it's possible for it to be in the diary."

"What do you mean? It's right there," said Lily.

"Copernicus couldn't have thought of these numbers," Wade went on. "It's an equation from modern physics."

"He said he met a man," Darrell said. "Besides, Copernicus was modern in the way he thought. He revolutionized science, didn't he?"

Wade suddenly figured out something that made his brain do an uncomfortable twist. He tried to iron it flat, but it wouldn't go. "It's just that . . . I don't get how Copernicus is writing this in 1514."