“We’ve got a triggering incident, too,” McGinnis said. “Turns out Gladstone was scheduled to fly out of Heathrow to New York last week, but they caught him drunk and he got the ax. And we just found his car, littered with parking tickets in the Locust Valley commuter lot.”

I nodded grimly. Now we were getting somewhere. Losing a job was high up there on the list of why people went on rampages.

“We have an arrest warrant yet?” I said.

“We will by the time we bag this skell’s sorry ass,” McGinnis said. “ESU’s waiting downstairs. Who’s up for a little trip to the Gold Coast?”

I shot up out of my chair with the rest of the surrounding cops, grinning. I’d never even touched my coffee, but for some reason I felt completely refreshed.

Locust Valley ’s town square seemed to consist solely of slate-roofed antiques shops, boutiques, and salons. Our designated staging area was a parking lot on Forest Avenue behind something called a “coach and motor works.” Call me a philistine, but it looked suspiciously like a gas station to me.

Nassau County Bureau of Special Operations and even some Suffolk County Emergency Service police were already there waiting for us. When a cop killer is involved, interdepartmental cooperation is more than a given.

“Morning, guys,” I said, and gathered everybody over by my car for a briefing.

The Nassau crew already had surveillance set up around Gladstone ’s four-acre property. There were no signs of activity there, and no one had gone in or out. Calls to the inside of his house were picked up by the answering machine. Gladstone had a wife named Erica and two co-ed daughters, I learned, but they hadn’t yet been located.

Tom Riley, the Nassau Special Ops lieutenant, tossed digital photos of the front and back of Gladstone ’s house onto the hood of my Chevy. The place was a gorgeous sprawling Tudor with a covered patio and a swimming pool in back. The landscaping was immaculate – Japanese maples, chrysanthemums, ornamental grasses. Definitely not the kind of house one usually associated with homicidal maniacs.

Studying the layout, we talked strategy about how to enter. There would be no attempt to negotiate. We’d gotten the arrest warrant, and we were going in. But considering the firepower Gladstone had, plus the fact that he’d already iced one cop and put another into a coma, no precaution was overlooked.

We decided that a breach team would storm the front door while snipers covered the narrow facing windows. If Gladstone showed his face in one, he’d be going down.

Since this was my case, I claimed the honor of following right behind the breach team to search the second floor.

“That door looks pretty solid,” I said. “What are you going to use? A battering ram?”

A young, muscular NYPD ESU sergeant held up a sawed-off shotgun and racked its slide.

“Brought my skeleton key,” he said, smiling around a chaw of tobacco. He actually seemed to be enjoying himself. I was glad he was on my side.

As the team geared up to start moving, I reached into my jacket and dropped another photograph onto the hood of the car. It was a picture of Tonya Griffith, the young woman transit cop Gladstone had murdered.

“Just a little reminder of why we all got out of bed this morning, gentlemen,” I said. “Let’s ring this scumbag’s bell.”

Gladstone ’s house was three blocks away, on a wooded street called Lattingtown Ridge Court. Our vehicles pulled out of the parking lot and cruised there, lights and sirens off.

As we arrived, I gave the green light over the radio. Two Emergency Service diesel trucks suddenly swerved into the driveway and across the lawn. A half-dozen tactical cops spilled out from behind them. Within seconds, I heard two crisp explosions – the front door hinges being shotgunned off.

As the cops shouldered the door aside and piled through it, yelling and tossing flashbangs, I flung open my car door and rushed in with them. I took the stairs two by two, with my Glock drawn and my heart pulsing like a strobe light.

“Police!” I screamed, kicking open the first closed door I encountered. It was a bathroom. There was nothing inside. Nobody. Curtain rings jingled as I ripped down the shower curtain. Just a shower caddy filled with shampoo bottles.

Damn! I thought, rushing back out into the hall, swinging my pistol from side to side.

Where was Gladstone?

The framed photographs of well-dressed, smiling people that lined the hallway rattled as I stormed along it.

“Police!” I yelled again. “We’re all over you, Gladstone. This is the police!”

At the far end was another door, this one slightly ajar. I tightened my grip on the Glock’s trigger and rammed the door with my shoulder.

It opened into a large, tray-ceilinged master bedroom suite. I cleared the corners first, scanned the bed, and…

My face jerked away in shock, as if I’d been punched. My gun almost slipped from my fingers before I managed to shove it back into its holster. Then I covered my nose and mouth with a hand as the vile coppery scent of blood and death washed over me.

We were too late.

This guy, I thought.

“Oh, my God,” a woman breathed from the hall behind me. It was Beth Peters, frozen with shock.

This guy.

I stepped out into the hall and got out my radio.

“Up here,” I said weakly. “Second floor.”

“Do you have him?” McGinnis yelled.

“No,” I said. “Not him.”

What we had was a bound, half-naked woman on the bed, drenched in a bloody sheet. Through the open doorway of the bathroom beyond I could see a woman’s foot hanging over the tub rim. Another young woman, a girl really, lay facedown in blood beside the toilet, hog-tied with lamp cord.

Shaking my head, I approached the bodies for a closer inspection. The two women in the bathroom were barely in their twenties. Both of them were completely naked. The woman in the bedroom was older – maybe their mother, Erica Gladstone. My gaze caught a wedding photo lying in a corner, its glass cracked from being knocked to the floor. I picked it up and held it beside her lifeless face. She was so battered, it took me a full minute to confirm it was a match.

I couldn’t believe it. Gladstone had shot and killed his wife and their two daughters. His own flesh and blood.

Other cops were coming into the room now. I could hear their exclamations of horror and disbelief behind me. I stayed where I was, staring at the blood-soaked carpet and sheets.

This was the worst crime of all, an atrocity, an outrage against humanity. God, I wanted to get my hands on this sick prick. Better yet, get him in the sights of my Glock.

It was eleven thirty A.M. when the Teacher stopped in front of an electronics store at 51st and Seventh. All the TVs that he could see through the big plate-glass windows were tuned to the Fox News Channel.

“Spree Killer Update,” scrolled across the top and, “Live from Locust Valley, Long Island ” across the bottom.

Hey, I know that place, he thought, smiling, as he watched the cops swarming on the lawn in front of the mansion.

Well, how about that? Score one for the gumshoes. They’d actually caught his scent. He’d started to wonder if they ever would.

But it didn’t really matter. He’d have to be a little more careful now, but he’d still be able to get all his work done. They were playing checkers while he was playing grand-master chess.

“Mommy, Mommy! Look, look!” a small Indian kid said as he pressed his face up against the store window in front of an Xbox 360. “Pokémon, Pikachu, Squirtle!” he cried.

His sari-clad mother slapped him on the backside before yanking him away down 51st.