There was a parking lot between the building and me. It was empty apart from a single vehicle, a Lexus SUV parked by the entrance. I checked ahead of me to where the road thinned further and turned into a track leading through fields. I didn’t have time to think, and on instinct I swung the wheel and headed toward the airstrip. My plan, such as it was, was to find someone to be with-preferably a group with whom I could mingle to protect me from my follower-but the Lexus was empty. As I got out of my car, I remembered seeing Anna here, standing by the Shapiros’ Range Rover. It was the airport where I’d landed in Harry’s Gulfstream, before it jetted away without me. That felt like a very long time ago.

I headed at a trot into the building to discover only an empty atrium with a flight of model aircraft hanging decoratively from its rafters. “Hello?” I shouted, walking to the side of the building nearest the strip. There was no reply, and I couldn’t see anyone in the offices by the hallway. I walked onto the tarmac and looked around. The aircraft I’d observed from the road had been parked and left for their owners’ eventual return. There was no sign of life on the runway.

Then I saw a dot in the distance above the fields and woods, and as it grew, I realized it was a helicopter approaching. I stood watching as it descended about thirty yards from me and settled on the ground. It was a dark green Sikorsky-a solid-looking beast-with two uniformed pilots. They waited for the blades to slow and then one took off his headphones, climbed out, and walked to the side of the aircraft, where he stood as a door opened and some steps folded down. An odd group emerged: a tall man, wearing a suit as if he’d come straight from the office, and two children-a girl and a boy, both maybe seven or eight years old. They were in tartan school uniforms and the boy had a tennis racket over his shoulder. The man waved briefly to the pilot and then the trio strolled across the tarmac toward me.

The pilot walked around the aircraft, his ceremonial duty done, and climbed back into the cockpit to start the engine again. By the time the party had reached me, the helicopter had lifted off into the sky, its passengers safely deposited.

“Excuse me,” I said as the man approached. “Could I speak to you?”

“What is it?” he said, slowing his walk slightly but not stopping as the children ran ahead into the building.

“I need help.”

I could see his eyes glaze over as he glanced at me, still moving, as if I were a loser whom he had to shake off.

“Sorry, buddy. Next time,” he said.

Before I could say anything else, he’d walked past me and through the building with the children. I trailed after him helplessly, as if drawn in his wake, and saw him raise the back gate of the Lexus to put the boy’s tennis racket inside before driving away. I stood there feeling dazed and humiliated. He’d just treated me as if I were some beggar in the street with a sob story about losing his MetroCard and needing a fare home. I suppose when you’re rich enough to commute to the Hamptons in a helicopter, every passerby looks like a panhandler.

Humiliation, however, wasn’t my biggest problem. As I looked up the hill after him, I saw another vehicle come through the trees and halt on the slope above me-the Mercedes. The driver paused, and I imagined him scanning the scene as I had done and then seeing my car-now the only one in the parking lot. I was still inside the building, so I probably wasn’t visible to him, but I soon would be.

I thought about my options and realized I didn’t have many. He was parked on top of the slope, cutting off the road down to the highway, and there was no one in the building to shield me. My car was a beacon signaling where I was. If I tried to get back in it and drive, I’d have to head either straight toward him or to the left along the dirt track and into the trees. He could easily seal the path behind me if I did that. Jogging back to the airstrip, I looked around for some means of escape. I couldn’t run on the tarmac, for I would be starkly visible on the flat landscape and he could catch me in his car. I looked to my right and saw a ditch by the side of the field that ran toward the trees. That ditch was the only cover I had.

I started up the hill, half running with my head down, hoping that he wouldn’t spot me. It was muddy and stony and I stumbled and half fell a few times, but I was making progress when I glanced over my right shoulder to see the Mercedes roar into life, speeding up the hill parallel with me. When it reached the brow, the door opened and a man in his twenties tumbled out and sprinted across the field toward me. My pursuer was tall and blond, and he covered ground very rapidly. He was solidly built, with wide shoulders and a thick waist, and stared at me as he ran as if he had plans to crush me. The good news was that he didn’t seem to be carrying a weapon. The bad news was that he didn’t look as though he needed one.

All I could think of was to keep going, to reach the woods. Maybe I’d lose him in the forest, where his size would give him trouble. I coughed and choked as I scrambled to make cover, but it was useless. He tackled me five yards from the trees. I felt his weight on me, as I had in Central Park, and we toppled into the undergrowth. He grabbed me in a headlock and dragged me roughly across the ground. The pressure on my neck was brutal; I thrashed wildly to force myself free.

He was hauling me into the forest, out of reach of rescue. I tried to shout, but only gurgles emerged from my mouth. Then we were in the trees and I felt one of my feet catch in a root. It only made him yank my shoulders harder, and I felt a shooting pain in my ankle as my foot sprang free. He dragged me ten yards into a clearing covered in leaves and twigs, and I felt the pressure slacken on my neck as he let me drop to the ground. I bent over, reaching for my neck, and as I did so, he kicked me in the ribs, as if finishing his assault. I shuddered with the pain of it and looked up at my assailant.

The last time I’d come across him, it had been dark and I hadn’t caught sight of his face. Now I saw him. He had blue eyes and a lean face with his mother’s nose. His blond hair was streaked and tousled as if he didn’t bother to keep it trimmed. He and Anna would have made a nice couple, I thought as he stood above me, panting with the effort he had put into pummeling me. It had come to me the night before, as I’d read about the Greene family. Their son, who worked at a hedge fund in New York after being shunted through the Ivy League, was called Nathan. It was just uncommon enough a name that I could remember the last time I’d heard it-from Anna, as she’d talked of her old boyfriend.

He was borderline, my therapist reckoned. He hooked me, and then made me suffer for loving him, she’d said.

Having witnessed the intimacy between her and Margaret Greene, I knew that was who it was. It had to be. Who else would have followed me after my meeting with Anna and trashed my apartment? It had to be someone with a grudge, and Nathan Greene had several. He had not only seen his old girlfriend kissing me, but he knew me as the psych who’d let Harry out of the hospital to kill his father. I’d remembered Rebecca’s old dress, slashed through from shoulders to waist. He must have believed it was Anna’s.

I had just enough time for the thoughts to pass through my head before Nathan dropped onto me, his knees pinning my shoulders to the ground and his body knocking away my breath. He put his hands around my neck in a throttle grip and squeezed. I was immobilized-his weight was enough to eliminate any thought of being able to struggle free-and I strained for breath.

“Murderer!” he shouted.

On his tortured face, I saw something that gave me hope. He was weeping. Tears were running out of his eyes and down his nose, and a couple dripped on the ground. He doesn’t want to kill me, I thought. He doesn’t know what he’s doing. I was only barely conscious, and I knew I didn’t have much time left. I summoned what energy I had and thrust my head sharply to one side while pushing up with my shoulders to release his grip.