Deterred from continuing into the Main Hall, Russo turned and limped in the direction of a set of swinging yellow doors, next to a tobacco shop whose sign read PRESIDENT CIGARS. The light coming through small windows on the doors beckoned him. To what? To safety?

The doors opened and a man in kitchen whites pushing a laundry cart came through, allowing the doors to close behind him. Russo looked back. The black man was following-casually, not in a rush it seemed, but following.

Russo’s heart tripped as he continued toward the doors. He thought of the handguns he’d never been without years ago, and wished he had one now. He would blast the black bastard into oblivion, he thought, save himself. You don’t mess with Louis Russo. But that bit of braggadocio was fleeting, displaced by palpable fear.

He was within ten feet of the doors now, and stopped again. The man had closed the gap, was only a few feet behind. Russo shoved against one of the two doors, causing it to open. The long hallway was brightly illuminated by overhead fluorescent fixtures, which momentarily blinded him. Ahead, men pushed service carts and carried trays to and from restaurants served by this off-limits employee area.

Russo took steps into the hallway and shouted at the men. “Hey, hey! Listen to me. I need-”

His voice was cut off by two shots from behind, the first striking him squarely between the shoulder blades, the second tearing a gaping hole in the back of his head. The force of the shots sent him pitching forward, cane and suitcase flying into the air. One of the workers in the hall who was carrying a large tray heaped with dirty dishes struggled with it. He lost control, the dishes smashing into pieces against the hard floor. Other workers looked at the black man, who’d covered the weapon he’d used with his trench coat but made no move to bolt from the scene.

“What the hell?” a worker yelled.

“Get him,” another shouted.

But no one approached Russo’s killer, who slowly went through the swinging doors, turned left into the Main Hall, and turned left again into the East Hall Gallery, where kiosks were open for business-a Radio Shack, a handbag shop, a U.S. Mint outlet, clothing and accessories kiosks, and one devoted to miniature replicas of Washington’s most famous buildings and monuments. All the kiosks were on wheels and could be rolled away when the East Hall was booked for receptions and other social events.

The man carrying the gun beneath his trench coat moved smoothly and quickly, but without a sense of urgency that might draw attention to him, past the kiosks and to an auxiliary entrance to the popular B. Smith’s restaurant, which led to a small bar area. People at the bar paid him no mind as he passed them and entered the main room.

“Table, sir?” he was asked by one of the restaurant’s maître d’s.

“No, thank you. Not today.”

He left the restaurant through its main entrance and stepped out onto Massachusetts Avenue, in front of Union Station, where taxis waited for and dropped off passengers, and a long line of tourist buses and trolleys stood ready to take visitors on tours of the nation’s capital. A large contingent of uniformed police, augmented by National Guard soldiers, patrolled the area. The Homeland Security Agency had recently elevated the colored alert system from yellow to orange; the city was blanketed by security forces.

He waited for a break in the traffic, crossed the wide boulevard, stopping for a second to observe a short, pudgy man playing a trumpet to entertain tourists and hopefully to have them drop money into the hat at his feet, circumvented the 1912 Columbus fountain depicting the Old and New Worlds and the adventurous Italian who’d linked the two, and stepped aboard an Old Town Trolley that was about to transport a dozen sweaty, ebullient tourists around the city.

“Ticket, sir?” he was asked.

“Didn’t have time to buy one inside,” he said, pulling out his wallet and handing money to the driver.

“Thank you, sir,” the driver said. “Welcome aboard. Great day for it.”

Once clear of the accident scene, Rich Marienthal drove as fast as he thought he could get away with. Of the many things Kathryn Jalick liked about him, his patience behind the wheel usually ranked high on the list. Not this day. He weaved in and out through traffic approaching the Key Bridge into Georgetown and on M Street until turning down Massachusetts Avenue.

“What a mess,” he said as they approached Union Station.

“Must be the terror alert,” she offered, referring to the legion of law enforcement personnel milling about the station. Cars were being prevented from pulling up directly in front, so Rich squeezed into a no-parking zone on First Street, at the side of the station.

“Wait here,” he told Kathryn as he bolted from the car and dodged traffic until he’d reached an entrance leading into the West Hall. Although uniformed armed guards patrolled that side of the station, too, no one was stopped from entering and exiting. Marienthal fought the urge to run as he made his way through the throngs of people to the gate area, looking for Russo. Failing to see him, he headed for the information desk in the Main Hall.

“I’m looking for an old Italian man,” he breathlessly told the woman at the desk. “I was supposed to meet his train from New York, but I got tied up in traffic-an accident in Virginia -and…”

The woman’s expression said she didn’t know what he expected her to do.

He went back into the train concourse, where a crowd had gathered in the east end of the station, in front of a tobacco shop. He managed to snake through the gathering until he could see activity next to the shop. Yellow crime-scene tape had been strung to create a wide off-limits area near a set of yellow swinging doors. A large contingent of uniformed and plainclothes police came and went through the doors, leading to what appeared to be a hallway.

“What’s going on?” Marienthal asked a bystander.

“Somebody died,” she said.

“Who?”

“I don’t know.”

“Somebody got shot,” said a man standing next to them.

“Shot?”

“I heard it,” yet another person said excitedly. “I was right here.”

“I heard it was an old guy with a cane.”

A male voice came through a bullhorn: “All right, all right, everybody stand back. There’s nothing to see. Please leave the area.”

Marienthal’s stomach tightened into a painful knot. He backed away until he was clear of the crowd and walked slowly toward the gate area where Russo would have left the Amtrak train. Although his eyes swept the station in search of the old man, he knew deep in his gut that he wouldn’t see him. “I heard it was an old guy with a cane,” the man in the crowd had said, and his words reverberated through Marienthal’s brain. It had to be Louis, he thought-he knew!

“Hey, man, they get the guy?” Joe Jenks asked Marienthal from the shoeshine stand.

“Huh?”

“The shooter. The guy who gunned down the old dude. They find him?”

“No, I… I don’t know.”

Marienthal stood by gate A-8 for what seemed a very long time before going to the Main Hall. He stepped outside and watched the police and military vehicles moving in and out of position. An antenna was extended high above the roof of a TV news remote truck with WTTG-Channel 5 emblazoned on its side. A reporter and cameraman prepared to beam a report back to the station.

“Any word on the victim’s name?” Marienthal asked, his voice weak.

The reporter, an attractive young woman holding a microphone and clipboard, turned to him and shook her head.

“Russo,” Marienthal said automatically. “Louis Russo.”

The reporter pulled a cell phone from where it was clipped on her belt and said into it, “I’ve got a witness who sounds like he knows the name of the victim. Russo, Louis Russo.” She listened intently for the reply. Once she’d received it, she turned to talk to Marienthal. But he was gone, back inside Union Station and on his way to where Kathryn waited for him in the car.