OUR LEGS pumping in unison, our breath coming in harsh rasps, Sampson and I climbed a dark marble stairway to the overhanging balcony. Uniformed officers and a couple of detectives were crouched in shooting positions up there.

I saw a detective from the train-station detail, which is normally a small-crimes unit. Nothing like this, nothing even close to dealing with a sharpshooting sniper.

“What do you know so far?” I asked. I thought the detective’s name was Vincent Mazzeo, but I wasn’t sure. He was pushing fifty and this was supposed to be a soft detail for him. I vaguely remembered that Mazzeo was supposed to be a pretty good guy.

“He’s inside one of those anterooms. See that door over there? The space he secured has no roof cover. Maybe we can get at him from above. What do you think?”

I glanced up toward the high gilded ceiling. I remembered that Union Station was supposed to be the largest covered colonnade in the United States. It sure looked it. Gary Soneji had always liked a big canvas. He had another one now.

The detective took something out of his shirt pocket. “I got a master key. This gets us into some of the antechambers. Maybe the room he’s in.”

I took the key. He wasn’t going to use it. He wasn’t going to play the hero. He didn’t want to meet up with Gary Soneji and his sharpshooter’s rifle this morning.

Another burst of gunfire suddenly came from the anteroom.

I counted. There were six-just like the last time.

Like a lot of psychos, Soneji was into codes, magical words, numbers. I wondered about sixes. Six, six, six? The number hadn’t come up in the past with him.

The shooting abruptly stopped again. Once more it was quiet in the station. My nerves were on edge, badly strained. There were too many people at risk here, too many to protect.

Sampson and I moved ahead. We were less than twenty feet from the anteroom where he was shooting. We pressed against the wall, Glocks out.

“You okay?” I whispered. We had been here before, similar bad situation, but that didn’t make it any better.

“This is fun shit, huh, Alex? First thing in the morning too. Haven’t even had my coffee and doughnut.”

“Next time he fires,” I said, “we go get him. He’s been firing six shots each time.”

“I noticed,” Sampson said without looking at me. He patted my leg. We took in big sips of air.

We didn’t have to wait long. Soneji began another volley of shots. Six shots. Why six shots each time?

He knew we’d be coming for him. Hell, he’d invited me to his shooting spree.

“Here we go,” I said.

We ran across the marble-and-stone corridor. I took out the key to the anteroom, squeezed it between my index finger and thumb.

I turned the key.

Click!

The door wouldn’t open! I jiggled the handle. Nothing.

“What the hell?” Sampson said behind me, anger in his voice. “What’s wrong with the door?”

“I just locked it,” I told him. “Soneji left it open for us.”

DOWNSTAIRS, a couple and two small children started to run. They rushed toward the glass doors and possible freedom. One of the kids tripped and went down hard on his knee. The mother dragged him forward. It was terrifying to watch, but they made it.

The firing started again!

Sampson and I burst into the anteroom, both of us crouched low, our guns drawn.

I caught a glimpse of a dark gray trap straight ahead.

A sniper rifle pointed out from the cover and camouflage of the trap. Soneji was underneath, hidden from view.

Sampson and I fired. Half a dozen gunshots thundered in the close quarters. Holes opened in the tarp. The rifle was silent.

I rushed across the small anteroom and ripped away the trap. I groaned-a deep, gut-wrenching sound.

No one was underneath the tarp. No Gary Soneji!

A Browning automatic rifle was strapped on a metal tripod. A timing device was attached to a rod and the trigger. The whole thing was customized. The rifle would fire at a programmed interval. Six shots, then a pause, then six more shots. No Gary Soneji.

I was already moving again. There were metal doors on the north and south walls of the small room. I yanked open the one closest to me. I expected a trap.

But the connecting space was empty. There was another gray metal door on the opposing wall. The door was shut. Gary Soneji still loved to play games. His favorite trick: He was the only one with the rules.

I rushed across the second room and opened door number two. Was that the game? A surprise? A booby prize behind either door one, two, or three?

I found myself peering inside another small space, another empty chamber. No Soneji. Not a sign of him anywhere.

The room had a metal stairway-it looked as if it went to another floor. Or maybe a crawl space above us.

I climbed the stairs, stopping and starting so he wouldn’t get a clear shot from above. My heart was pounding, my legs trembling. I hoped that Sampson was close behind. I needed cover.

At the top of the stairway, a hatchway was open. No Gary Soneji here either. I had been lured deeper and deeper into some kind of trap, into his web.

My stomach was rolling. I felt a sharp pain building up behind my eyes. Soneji was still somewhere in Union Station. He had to be. He’d said he wanted to see me.

SONEJI SAT as calm as a small-town banker, pretending to read the Washington Post on the 8:45 A.M. Metroliner to Penn Station in New York. His heart was still palpitating, but none of the excitement showed on his face. He wore a gray suit, white shirt, striped blue tie-he looked just like all the rest of the commuter assholes.

He had just tripped the light fantastic, hadn’t he? He had gone where few others ever would have dared. He had just outdone the legendary Charles Whitman, and this was only the beginning of his prime-time exposure. There was a saying he liked a lot. Victory belongs to the player who makes the next-to-last mistake.

Soneji drifted in and out of a reverie in which he returned to his beloved woods around Princeton, New Jersey. He could see himself as a boy again. He remembered everything about the dense, uneven, but often spectacularly beautiful terrain. When he was eleven, he had stolen a.22-caliber rifle from one of the surrounding farms. He kept it hidden in a rock quarry near his house. The gun was carefully wrapped in an oilcloth, foil, and burlap bags. The.22-caliber rifle was the only earthly possession that he cared about, the only thing that was truly his.

He remembered how he would scale down a steep, very rocky ravine to a quiet place where the forest floor leveled off, just past a thick tangle of bayberry prickers. There was a clearing in the hollow, and this was the site of his secret, forbidden target practice in those early years. One day he brought a rabbit’s head and a calico cat from the nearby Ruocco farm. There wasn’t much that a cat liked more than a fresh rabbit’s head. Cats were such little ghouls. Cats were like him. To this day, they were magical for him. The way they stalked and hunted was the greatest. That was why he had given one to Dr. Cross and his family.

Little Rosie.

After he had placed the severed bunny’s head in the center of the clearing, he untied the neck of the burlap bag and let the kitty free. Even though he had punched a few airholes in the bag, the cat had almost suffocated. “Sic ’em. Sic the bunny!” he commanded. The cat caught the scent of the fresh kill and took off in a pouncing run. Gary put the.22 rifle on his shoulder and watched. He sighted on the moving target. He caressed the trigger of his deuce-deuce, and then he fired. He was learning how to kill.

You’re such an addict! He chastised himself now, back in the present, on the Metroliner train. Little had changed since he’d been the original Bad Boy in the Princeton area. His stepmother-the gruesome and untalented whore of Babylon -used to lock him in the basement regularly back then. She would leave him alone in the dark, sometimes for as long as ten to twelve hours. He learned to love the darkness, to be the darkness. He learned to love the cellar, to make it his favorite place in the world.