Sitting in the passenger seat of the lead car, Olivetti turned backward toward Langdon and Vittoria. His eyes were filled with rage. "You assured me a sound explanation, andthis is what I get?"

Langdon resisted the urge to pull Folio 5 from his pocket and wave it in Olivetti's face. "All I know is that the information we found refers to Raphael's tomb, and Raphael's tomb is inside the Pantheon."

The four unmarked Alpha Romeo 155 T-Sparks roared down Via dei Coronari like fighter jets off a runway. The vehicles carried twelve plainclothed Swiss Guards armed with Cherchi-Pardini semiautomatics, local-radius nerve gas canisters, and long-range stun guns. The three sharpshooters carried laser-sighted rifles.

Langdon felt cramped in the small car. "I understand your --"

"No, you don't understand!" Olivetti never raised his voice, but his intensity tripled. "I have just removed a dozen of my best men from Vatican City on the eve of conclave. And I have done this to stake out the Pantheon based on the testimony of some American I have never met who has just interpreted a four-hundred-year-old poem. I have also just left the search for this antimatter weapon in the hands of secondary officers."

"I don't know," Langdon said. "But the Illuminati are obviously highly resourceful. They've broken into both CERN and Vatican City. It's only by luck that we know where the first kill zone is. The Pantheon is your one chance to catch this guy."

The officer behind the wheel nodded. "He's right, commander. My wife and I --"

"I had hoped so," Langdon said. "And wewould have… a century ago."

"Drive," Olivetti snapped. He turned back to Langdon. "How could a killer accomplish an assassination in such a crowded place and escape unseen?"

"More contradictions," Olivetti said."One chance? I thought you said there was some sort of pathway. A series of markers. If the Pantheon is the right spot, we can follow the pathway to the other markers. We will havefour chances to catch this guy."

Langdon's realization that the Pantheon was the first altar of science had been a bittersweet moment. History had a way of playing cruel tricks on those who chased it. It was a long shot that the Path of Illumination would be intact after all of these years, with all of its statues in place, but part of Langdon had fantasized about following the path all the way to the end and coming face to face with the sacred Illuminati lair. Alas, he realized, it was not to be. "The Vatican had all the statues in the Pantheon removed and destroyed in the late 1800s."

"Any hope," Vittoria said, "of finding the Path of Illumination and additional markers?"

Vittoria looked shocked. "Why?"

The driver swerved the car toward the curb and put on the brakes. Three other Alpha Romeos skidded in behind them. The Swiss Guard convoy screeched to a halt.

Olivetti stared at them both a long moment and then turned and faced front. "Pull over," he barked to the driver.

"My job," Olivetti said, turning in his seat, his voice like stone. "Mr. Langdon, when you told me you would explain the situation en route, I assumed I would be approaching the Pantheon with a clear idea of why my men are here. That is not the case. Because I am abandoning critical duties by being here, and because I have found very little that makes sense in this theory of yours about virgin sacrifices and ancient poetry, I cannot in good conscience continue. I am recalling this mission immediately." He pulled out his walkie-talkie and clicked it on.

"The statues were pagan Olympian Gods. Unfortunately, that means the first marker is gone… and with it --"

Langdon shook his head. "We haveone shot. The Pantheon. After that, the path disappears."

"What are you doing!" Vittoria demanded.

Vittoria reached across the seat and grabbed his arm. "You can't!"

"No, but I --"

Olivetti slammed down the walkie-talkie and fixed her with a red-hot stare. "Have you been to the Pantheon, Ms. Vetra?"

"Your point?" she said coolly.

"My point?" Olivetti's knuckles gripped the seat. "My point is that what you have just told me is going to happen is utterly impossible! Can you give me one plausible scenario of how someone could kill a cardinalinside the Pantheon? How does one even get a hostage past the guardsinto the Pantheon in the first place? Much less actually kill him and get away?" Olivetti leaned over the seat, his coffee breath now in Langdon's face. "How, Mr. Langdon? One plausible scenario."

"Let me tell you something about it. The Pantheon is a single room. A circular cell made of stone and cement. It hasone entrance. No windows. Onenarrow entrance. That entrance is flanked at all times by no less than four armed Roman policemen who protect this shrine from art defacers, anti-Christian terrorists, and gypsy tourist scams."

"Onescenario?" Vittoria quipped, her voice unruffled. "How about this? The killer flies over in a helicopter and drops a screaming, branded cardinal down through the hole in the roof. The cardinal hits the marble floor and dies."

"I heard you," Olivetti said. "Enough." He took a deep breath and blew it out. Someone rapped sharply on the window, and everyone jumped. It was a soldier from one of the other cars. Olivetti rolled down the window.

Olivetti frowned. "Possible, I admit… but hardly --"

Langdon felt the tiny car shrink around him. I have no idea! I'm not an assassin! I don't know how he will do it! I only know --

Everyone in the car turned and stared at Vittoria. Langdon didn't know what to think. You've got one sick imagination, lady, but you are quick.

"Or the killer drugs the cardinal," Vittoria said, "brings him to the Pantheon in a wheelchair like some old tourist. He wheels him inside, quietly slits his throat, and then walks out."

Not bad! Langdon thought.

This seemed to wake up Olivetti a bit.

"Or," she said, "the killer could --"

Langdon gave Vittoria an impressed nod. She smiled back, and for an instant Langdon felt an unexpected connection… a thread of magnetism between them.

"Very good, sir." The soldier returned to his car.

Olivetti nodded vaguely but said nothing for many moments. He ran a finger back and forth across the dash, making a line in the dust. He studied Langdon in the side-view mirror, and Langdon felt himself being measured and weighed. Finally Olivetti turned back to the guard. There was reluctance in his voice. "I'll want separate approaches. Cars to Piazza della Rotunda, Via delgi Orfani, Piazza Sant"Ignacio, and Sant"Eustachio. No closer than two blocks. Once you're parked, gear up and await my orders. Three minutes."

"Everything all right, commander?" The soldier was dressed in street clothes. He pulled back the sleeve of his denim shirt to reveal a black chronograph military watch. "Seven-forty, commander. We'll need time to get in position."

The commander turned in his seat and locked eyes with Langdon. "Mr. Langdon, this had better not blow up in our faces."

Langdon smiled uneasily. How could it?